diff --git a/Avalonia.Desktop.slnf b/Avalonia.Desktop.slnf
index 92c924f107..5e770a0170 100644
--- a/Avalonia.Desktop.slnf
+++ b/Avalonia.Desktop.slnf
@@ -39,14 +39,13 @@
       "src\\Markup\\Avalonia.Markup.Xaml\\Avalonia.Markup.Xaml.csproj",
       "src\\Markup\\Avalonia.Markup\\Avalonia.Markup.csproj",
       "src\\Skia\\Avalonia.Skia\\Avalonia.Skia.csproj",
-      "src\\tools\\Avalonia.Generators\\Avalonia.Generators.csproj",
-      "src\\tools\\Avalonia.Generators\\Avalonia.Generators.csproj",
-      "src\\tools\\DevAnalyzers\\DevAnalyzers.csproj",
-      "src\\tools\\DevGenerators\\DevGenerators.csproj",
-      "src\\tools\\PublicAnalyzers\\Avalonia.Analyzers.csproj",
       "src\\Windows\\Avalonia.Direct2D1\\Avalonia.Direct2D1.csproj",
       "src\\Windows\\Avalonia.Win32.Interop\\Avalonia.Win32.Interop.csproj",
       "src\\Windows\\Avalonia.Win32\\Avalonia.Win32.csproj",
+      "src\\tools\\Avalonia.Analyzers\\Avalonia.Analyzers.csproj",
+      "src\\tools\\Avalonia.Generators\\Avalonia.Generators.csproj",
+      "src\\tools\\DevAnalyzers\\DevAnalyzers.csproj",
+      "src\\tools\\DevGenerators\\DevGenerators.csproj",
       "tests\\Avalonia.Base.UnitTests\\Avalonia.Base.UnitTests.csproj",
       "tests\\Avalonia.Benchmarks\\Avalonia.Benchmarks.csproj",
       "tests\\Avalonia.Controls.DataGrid.UnitTests\\Avalonia.Controls.DataGrid.UnitTests.csproj",
@@ -66,4 +65,4 @@
       "tests\\Avalonia.UnitTests\\Avalonia.UnitTests.csproj"
     ]
   }
-}
+}
\ No newline at end of file
diff --git a/build/SharedVersion.props b/build/SharedVersion.props
index 2849262591..3239ca830a 100644
--- a/build/SharedVersion.props
+++ b/build/SharedVersion.props
@@ -4,7 +4,7 @@
     <Product>Avalonia</Product>
     <Version>11.0.999</Version>
     <Authors>Avalonia Team</Authors>
-    <Copyright>Copyright 2022 &#169; The AvaloniaUI Project</Copyright>
+    <Copyright>Copyright 2013-$([System.DateTime]::Now.ToString(`yyyy`)) &#169; The AvaloniaUI Project</Copyright>
     <PackageProjectUrl>https://avaloniaui.net</PackageProjectUrl>
     <RepositoryUrl>https://github.com/AvaloniaUI/Avalonia/</RepositoryUrl>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
diff --git a/nukebuild/Build.cs b/nukebuild/Build.cs
index 87e1e86bf9..524c9fa4e4 100644
--- a/nukebuild/Build.cs
+++ b/nukebuild/Build.cs
@@ -312,7 +312,7 @@ partial class Build : NukeBuild
 
     public static int Main() =>
         RuntimeInformation.IsOSPlatform(OSPlatform.Windows)
-            ? Execute<Build>(x => x.RunToolsTests)
+            ? Execute<Build>(x => x.Package)
             : Execute<Build>(x => x.RunTests);
 
 }
diff --git a/nukebuild/RefAssemblyGenerator.cs b/nukebuild/RefAssemblyGenerator.cs
index e1c19c69a3..54e428c442 100644
--- a/nukebuild/RefAssemblyGenerator.cs
+++ b/nukebuild/RefAssemblyGenerator.cs
@@ -71,10 +71,10 @@ public class RefAssemblyGenerator
         foreach (var nested in type.NestedTypes)
             ProcessType(nested, obsoleteCtor);
 
-        var hideMethods = (type.IsInterface && type.Name.EndsWith("Impl"))
+        var hideMembers = (type.IsInterface && type.Name.EndsWith("Impl"))
                           || HasPrivateApi(type.CustomAttributes);
 
-        var injectMethod = hideMethods
+        var injectMethod = hideMembers
                            || type.CustomAttributes.Any(a =>
                                a.AttributeType.FullName == "Avalonia.Metadata.NotClientImplementableAttribute");
 
@@ -95,21 +95,57 @@ public class RefAssemblyGenerator
 
         foreach (var m in type.Methods)
         {
-            if (hideMethods || HasPrivateApi(m.CustomAttributes))
+            if (hideMembers || HasPrivateApi(m.CustomAttributes))
             {
-                var dflags = MethodAttributes.Public | MethodAttributes.Family | MethodAttributes.FamORAssem |
-                             MethodAttributes.FamANDAssem | MethodAttributes.Assembly;
-                m.Attributes = ((m.Attributes | dflags) ^ dflags) | MethodAttributes.Assembly;
+                HideMethod(m);
             }
             MarkAsUnstable(m, obsoleteCtor, forceUnstable);
         }
 
+        foreach (var p in type.Properties)
+        {
+            if (HasPrivateApi(p.CustomAttributes))
+            {
+                if (p.SetMethod != null)
+                    HideMethod(p.SetMethod);
+                if (p.GetMethod != null)
+                    HideMethod(p.GetMethod);
+            }
+        }
+
+        foreach (var f in type.Fields)
+        {
+            if (hideMembers || HasPrivateApi(f.CustomAttributes))
+            {
+                var dflags = FieldAttributes.Public | FieldAttributes.Family | FieldAttributes.FamORAssem |
+                             FieldAttributes.FamANDAssem | FieldAttributes.Assembly;
+                f.Attributes = ((f.Attributes | dflags) ^ dflags) | FieldAttributes.Assembly;
+            }
+        }
+
+        foreach (var cl in type.NestedTypes)
+        {
+            ProcessType(cl, obsoleteCtor);
+            if (hideMembers)
+            {
+                var dflags = TypeAttributes.Public;
+                cl.Attributes = ((cl.Attributes | dflags) ^ dflags) | TypeAttributes.NotPublic;
+            }
+        }
+
         foreach (var m in type.Properties)
             MarkAsUnstable(m, obsoleteCtor, forceUnstable);
         foreach (var m in type.Events)
             MarkAsUnstable(m, obsoleteCtor, forceUnstable);
     }
 
+    static void HideMethod(MethodDefinition m)
+    {
+        var dflags = MethodAttributes.Public | MethodAttributes.Family | MethodAttributes.FamORAssem |
+                     MethodAttributes.FamANDAssem | MethodAttributes.Assembly;
+        m.Attributes = ((m.Attributes | dflags) ^ dflags) | MethodAttributes.Assembly;
+    }
+    
     static void MarkAsUnstable(IMemberDefinition def, MethodReference obsoleteCtor, ICustomAttribute unstableAttribute)
     {
         if (def.CustomAttributes.Any(a => a.AttributeType.FullName == "System.ObsoleteAttribute"))
diff --git a/samples/ControlCatalog.NetCore/ControlCatalog.NetCore.csproj b/samples/ControlCatalog.NetCore/ControlCatalog.NetCore.csproj
index 877d475fb6..37719b77d8 100644
--- a/samples/ControlCatalog.NetCore/ControlCatalog.NetCore.csproj
+++ b/samples/ControlCatalog.NetCore/ControlCatalog.NetCore.csproj
@@ -16,6 +16,7 @@
 
   <ItemGroup>
     <Compile Include="..\..\src\Avalonia.X11\NativeDialogs\Gtk.cs" Link="NativeControls\Gtk\Gtk.cs" />
+    <Compile Include="..\..\src\Avalonia.Base\Platform\Interop\Utf8Buffer.cs" Link="NativeControls\Utf8Buffer.cs" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/samples/ControlCatalog/MainView.xaml.cs b/samples/ControlCatalog/MainView.xaml.cs
index 9c511f9eb0..801844a43c 100644
--- a/samples/ControlCatalog/MainView.xaml.cs
+++ b/samples/ControlCatalog/MainView.xaml.cs
@@ -83,9 +83,10 @@ namespace ControlCatalog
                 if (transparencyLevels.SelectedItem is WindowTransparencyLevel selected)
                 {
                     var topLevel = (TopLevel)this.GetVisualRoot()!;
-                    topLevel.TransparencyLevelHint = selected;
+                    topLevel.TransparencyLevelHint = new[] { selected };
 
-                    if (selected != WindowTransparencyLevel.None)
+                    if (topLevel.ActualTransparencyLevel != WindowTransparencyLevel.None &&
+                        topLevel.ActualTransparencyLevel == selected)
                     {
                         var transparentBrush = new ImmutableSolidColorBrush(Colors.White, 0);
                         var semiTransparentBrush = new ImmutableSolidColorBrush(Colors.Gray, 0.2);
diff --git a/samples/ControlCatalog/Pages/ContextMenuPage.xaml.cs b/samples/ControlCatalog/Pages/ContextMenuPage.xaml.cs
index 96fcb54650..664264956f 100644
--- a/samples/ControlCatalog/Pages/ContextMenuPage.xaml.cs
+++ b/samples/ControlCatalog/Pages/ContextMenuPage.xaml.cs
@@ -19,8 +19,8 @@ namespace ControlCatalog.Pages
             customContextRequestedBorder.AddHandler(ContextRequestedEvent, CustomContextRequested, RoutingStrategies.Tunnel);
 
             var cancellableContextBorder = this.Get<Border>("CancellableContextBorder");
-            cancellableContextBorder.ContextMenu!.ContextMenuClosing += ContextFlyoutPage_Closing;
-            cancellableContextBorder.ContextMenu!.ContextMenuOpening += ContextFlyoutPage_Opening;
+            cancellableContextBorder.ContextMenu!.Closing += ContextFlyoutPage_Closing;
+            cancellableContextBorder.ContextMenu!.Opening += ContextFlyoutPage_Opening;
         }
 
         private ContextPageViewModel? _model;
diff --git a/samples/ControlCatalog/Pages/DialogsPage.xaml.cs b/samples/ControlCatalog/Pages/DialogsPage.xaml.cs
index 971a6a6718..4d617fd313 100644
--- a/samples/ControlCatalog/Pages/DialogsPage.xaml.cs
+++ b/samples/ControlCatalog/Pages/DialogsPage.xaml.cs
@@ -307,7 +307,7 @@ namespace ControlCatalog.Pages
             Content:
             ";
 
-                        resultText += await ReadTextFromFile(file, 10000);
+                        resultText += await ReadTextFromFile(file, 500);
                     }
 
                     openedFileContent.Text = resultText;
diff --git a/samples/ControlCatalog/Pages/ItemsRepeaterPage.xaml.cs b/samples/ControlCatalog/Pages/ItemsRepeaterPage.xaml.cs
index 70ce6107ad..2219966daa 100644
--- a/samples/ControlCatalog/Pages/ItemsRepeaterPage.xaml.cs
+++ b/samples/ControlCatalog/Pages/ItemsRepeaterPage.xaml.cs
@@ -117,9 +117,8 @@ namespace ControlCatalog.Pages
         private void ScrollTo(int index)
         {
             System.Diagnostics.Debug.WriteLine("Scroll to " + index);
-            var layoutManager = ((TopLevel)VisualRoot!).LayoutManager;
             var element = _repeater.GetOrCreateElement(index);
-            layoutManager.ExecuteLayoutPass();
+            ((TopLevel)VisualRoot!).UpdateLayout();
             element.BringIntoView();
         }
 
diff --git a/samples/ControlCatalog/Pages/TabControlPage.xaml b/samples/ControlCatalog/Pages/TabControlPage.xaml
index 3a2464e9fd..1faa74c1ce 100644
--- a/samples/ControlCatalog/Pages/TabControlPage.xaml
+++ b/samples/ControlCatalog/Pages/TabControlPage.xaml
@@ -4,7 +4,27 @@
     xmlns="https://github.com/avaloniaui"
     xmlns:viewModels="using:ControlCatalog.ViewModels"
     x:DataType="viewModels:TabControlPageViewModel">
-    <DockPanel>
+    <DockPanel Classes.WithContentTemplates="{Binding IsChecked, ElementName=UseContentTemplates}">
+        <DockPanel.Styles>
+            <Style Selector="DockPanel.WithContentTemplates">
+                <Style Selector="^ TabItem">
+                    <Setter Property="ContentTemplate">
+                        <DataTemplate x:CompileBindings="False">
+                            <Border BorderBrush="Red" BorderThickness="10">
+                                <ContentPresenter Content="{Binding}"/>
+                            </Border>
+                        </DataTemplate>
+                    </Setter>
+                </Style>
+                <Style Selector="^ TabControl">
+                    <Setter Property="ContentTemplate">
+                        <DataTemplate>
+                            <TextBlock Text="This template should be overriden by each TabItem's template."/>
+                        </DataTemplate>
+                    </Setter>
+                </Style>
+            </Style>
+        </DockPanel.Styles>
         <TextBlock 
             DockPanel.Dock="Top" 
             Classes="h2"
@@ -55,14 +75,14 @@
                     Margin="0 16"
                     DisplayMemberBinding="{Binding Header, x:DataType=viewModels:TabControlPageViewModelItem}"
                     TabStripPlacement="{Binding TabPlacement}">
-                    <TabControl.ContentTemplate>
+                    <TabControl.DataTemplates>
                         <DataTemplate x:DataType="viewModels:TabControlPageViewModelItem">
                             <StackPanel Orientation="Vertical" Spacing="8">
                                 <TextBlock Text="{Binding Text}"/>
                                 <Image Source="{Binding Image}" Width="300"/>
                             </StackPanel>
                         </DataTemplate>
-                    </TabControl.ContentTemplate>
+                    </TabControl.DataTemplates>
                     <TabControl.Styles>
                         <Style Selector="TabItem" x:DataType="viewModels:TabControlPageViewModelItem">
                             <Setter Property="IsEnabled" Value="{Binding IsEnabled}"/>
@@ -78,12 +98,13 @@
                 HorizontalAlignment="Center"
                 VerticalAlignment="Center">
                 <TextBlock VerticalAlignment="Center">Tab Placement:</TextBlock>
-                <ComboBox SelectedIndex="{Binding TabPlacement, Mode=TwoWay}">
+                <ComboBox SelectedIndex="{Binding TabPlacement, Mode=TwoWay}" Width="100">
                     <ComboBoxItem>Left</ComboBoxItem>
                     <ComboBoxItem>Bottom</ComboBoxItem>
                     <ComboBoxItem>Right</ComboBoxItem>
                     <ComboBoxItem>Top</ComboBoxItem>
                 </ComboBox>
+                <CheckBox Name="UseContentTemplates">Set TabItem.ContentTemplate</CheckBox>
             </StackPanel>
         </Grid>
     </DockPanel>
diff --git a/samples/GpuInterop/MainWindow.axaml.cs b/samples/GpuInterop/MainWindow.axaml.cs
index 7cf0bc00e2..8d359fe7ef 100644
--- a/samples/GpuInterop/MainWindow.axaml.cs
+++ b/samples/GpuInterop/MainWindow.axaml.cs
@@ -11,7 +11,7 @@ namespace GpuInterop
         {
             InitializeComponent();
             this.AttachDevTools();
-            Renderer.Diagnostics.DebugOverlays = RendererDebugOverlays.Fps;
+            RendererDiagnostics.DebugOverlays = RendererDebugOverlays.Fps;
         }
 
         private void InitializeComponent()
diff --git a/samples/IntegrationTestApp/MainWindow.axaml.cs b/samples/IntegrationTestApp/MainWindow.axaml.cs
index 7130b3602a..689cfcb65d 100644
--- a/samples/IntegrationTestApp/MainWindow.axaml.cs
+++ b/samples/IntegrationTestApp/MainWindow.axaml.cs
@@ -136,7 +136,7 @@ namespace IntegrationTestApp
                 Name = "TransparentWindow",
                 SystemDecorations = SystemDecorations.None,
                 Background = Brushes.Transparent,
-                TransparencyLevelHint = WindowTransparencyLevel.Transparent,
+                TransparencyLevelHint = new[] { WindowTransparencyLevel.Transparent },
                 WindowStartupLocation = WindowStartupLocation.CenterOwner,
                 Width = 200,
                 Height = 200,
diff --git a/samples/MobileSandbox.Desktop/MobileSandbox.Desktop.csproj b/samples/MobileSandbox.Desktop/MobileSandbox.Desktop.csproj
index 31a6b05175..c1d157a2e8 100644
--- a/samples/MobileSandbox.Desktop/MobileSandbox.Desktop.csproj
+++ b/samples/MobileSandbox.Desktop/MobileSandbox.Desktop.csproj
@@ -4,37 +4,16 @@
     <OutputType>WinExe</OutputType>
     <TargetFramework>net6.0</TargetFramework>
     <TargetLatestRuntimePatch>true</TargetLatestRuntimePatch>
-    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-  </PropertyGroup>
-
-  <PropertyGroup Condition="'$(RunNativeAotCompilation)' == 'true'">
-    <IlcTrimMetadata>true</IlcTrimMetadata>
-    <RestoreAdditionalProjectSources>https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet7/nuget/v3/index.json</RestoreAdditionalProjectSources>
-    <NativeAotCompilerVersion>7.0.0-*</NativeAotCompilerVersion>
   </PropertyGroup>
 
-  <ItemGroup>
-    <Compile Include="..\..\src\Avalonia.X11\NativeDialogs\Gtk.cs" Link="NativeControls\Gtk\Gtk.cs" />
-  </ItemGroup>
-
   <ItemGroup>
     <ProjectReference Include="..\..\src\Avalonia.Diagnostics\Avalonia.Diagnostics.csproj" />
-    <ProjectReference Include="..\..\src\Headless\Avalonia.Headless.Vnc\Avalonia.Headless.Vnc.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.Dialogs\Avalonia.Dialogs.csproj" />
-    <ProjectReference Include="..\..\src\Linux\Avalonia.LinuxFramebuffer\Avalonia.LinuxFramebuffer.csproj" />
     <ProjectReference Include="..\MobileSandbox\MobileSandbox.csproj" />
-    <ProjectReference Include="..\..\src\Avalonia.X11\Avalonia.X11.csproj" />
     <!-- For native controls test -->
     <PackageReference Include="MonoMac.NetStandard" Version="0.0.4" />
   </ItemGroup>
 
-  <ItemGroup Condition="'$(RunNativeAotCompilation)' == 'true'">
-    <PackageReference Include="Microsoft.DotNet.ILCompiler" Version="$(NativeAotCompilerVersion)" />
-    <!-- Cross-compilation for Windows x64-arm64 and Linux x64-arm64 -->
-    <PackageReference Condition="'$(RuntimeIdentifier)'=='win-arm64'" Include="runtime.win-x64.Microsoft.DotNet.ILCompiler" Version="$(NativeAotCompilerVersion)" />
-    <PackageReference Condition="'$(RuntimeIdentifier)'=='linux-arm64'" Include="runtime.linux-x64.Microsoft.DotNet.ILCompiler" Version="$(NativeAotCompilerVersion)" />
-  </ItemGroup>
-
   <PropertyGroup>
     <!-- For Microsoft.CodeAnalysis -->
     <SatelliteResourceLanguages>en</SatelliteResourceLanguages>
diff --git a/samples/MobileSandbox/MobileSandbox.csproj b/samples/MobileSandbox/MobileSandbox.csproj
index 0d7c7859f8..7fa364da9b 100644
--- a/samples/MobileSandbox/MobileSandbox.csproj
+++ b/samples/MobileSandbox/MobileSandbox.csproj
@@ -14,9 +14,6 @@
     <AvaloniaResource Include="Assets\*" />
     <AvaloniaResource Include="Assets\Fonts\*" />
   </ItemGroup>
-  <ItemGroup>
-    <None Remove="Pages\NativeEmbedPage.xaml" />
-  </ItemGroup>
   <ItemGroup>
     <EmbeddedResource Include="Assets\Fonts\SourceSansPro-Bold.ttf" />
     <EmbeddedResource Include="Assets\Fonts\SourceSansPro-BoldItalic.ttf" />
@@ -34,17 +31,5 @@
     <ProjectReference Include="..\SampleControls\ControlSamples.csproj" />
   </ItemGroup>
 
-  <ItemGroup>
-    <AvaloniaResource Update="Pages\NativeEmbedPage.xaml">
-      <Generator>MSBuild:Compile</Generator>
-    </AvaloniaResource>
-  </ItemGroup>
-
-  <ItemGroup>
-    <Compile Update="Pages\NativeEmbedPage.xaml.cs">
-      <DependentUpon>%(Filename)</DependentUpon>
-    </Compile>
-  </ItemGroup>
-
   <Import Project="..\..\build\BuildTargets.targets" />
 </Project>
diff --git a/samples/RenderDemo/MainWindow.xaml.cs b/samples/RenderDemo/MainWindow.xaml.cs
index d85f3b6051..be47ffd6e9 100644
--- a/samples/RenderDemo/MainWindow.xaml.cs
+++ b/samples/RenderDemo/MainWindow.xaml.cs
@@ -21,7 +21,7 @@ namespace RenderDemo
             void BindOverlay(Expression<Func<MainWindowViewModel, bool>> expr, RendererDebugOverlays overlay)
                 => vm.WhenAnyValue(expr).Subscribe(x =>
                 {
-                    var diagnostics = Renderer.Diagnostics;
+                    var diagnostics = RendererDiagnostics;
                     diagnostics.DebugOverlays = x ?
                         diagnostics.DebugOverlays | overlay :
                         diagnostics.DebugOverlays & ~overlay;
diff --git a/samples/RenderDemo/Pages/AnimationsPage.xaml b/samples/RenderDemo/Pages/AnimationsPage.xaml
index d764af8978..f80389c832 100644
--- a/samples/RenderDemo/Pages/AnimationsPage.xaml
+++ b/samples/RenderDemo/Pages/AnimationsPage.xaml
@@ -347,12 +347,8 @@
   </UserControl.Styles>
   <Grid>
     <StackPanel HorizontalAlignment="Center" VerticalAlignment="Center" ClipToBounds="False">
-      <StackPanel.Clock>
-        <Clock />
-      </StackPanel.Clock>
       <StackPanel Orientation="Horizontal" VerticalAlignment="Center" Spacing="20">
         <TextBlock VerticalAlignment="Center">Hover to activate Keyframe Animations.</TextBlock>
-        <Button Content="{Binding PlayStateText}" Command="{Binding TogglePlayState}" Click="ToggleClock" />
       </StackPanel>
       <WrapPanel ClipToBounds="False">
         <Border Classes="Test Rect1" Background="DarkRed"/>
diff --git a/samples/RenderDemo/Pages/AnimationsPage.xaml.cs b/samples/RenderDemo/Pages/AnimationsPage.xaml.cs
index 2195b3d494..fc28f64021 100644
--- a/samples/RenderDemo/Pages/AnimationsPage.xaml.cs
+++ b/samples/RenderDemo/Pages/AnimationsPage.xaml.cs
@@ -24,20 +24,5 @@ namespace RenderDemo.Pages
         {
             AvaloniaXamlLoader.Load(this);
         }
-
-        private void ToggleClock(object sender, RoutedEventArgs args)
-        {
-            var button = sender as Button;
-            var clock = button.Clock;
-
-            if (clock.PlayState == PlayState.Run)
-            {
-                clock.PlayState = PlayState.Pause;
-            }
-            else if (clock.PlayState == PlayState.Pause)
-            {
-                clock.PlayState = PlayState.Run;
-            }
-        }
     }
 }
diff --git a/samples/RenderDemo/Pages/CustomAnimatorPage.xaml b/samples/RenderDemo/Pages/CustomAnimatorPage.xaml
index 0c625b6a77..25379ba13a 100644
--- a/samples/RenderDemo/Pages/CustomAnimatorPage.xaml
+++ b/samples/RenderDemo/Pages/CustomAnimatorPage.xaml
@@ -11,10 +11,18 @@
           <Style.Animations>
             <Animation Duration="0:0:1" IterationCount="Infinite">
               <KeyFrame Cue="0%">
-                <Setter Property="Text" Value="" Animation.Animator="{x:Type pages:CustomStringAnimator}"/>
+                <Setter Property="Text" Value="">
+                  <Animation.Animator>
+                    <pages:CustomStringAnimator/>
+                  </Animation.Animator>
+                </Setter>
               </KeyFrame>
               <KeyFrame Cue="100%">
-                <Setter Property="Text" Value="0123456789" Animation.Animator="{x:Type pages:CustomStringAnimator}"/>
+                <Setter Property="Text" Value="0123456789" >
+                  <Animation.Animator>
+                    <pages:CustomStringAnimator/>
+                  </Animation.Animator>
+                </Setter>
               </KeyFrame>
             </Animation>
           </Style.Animations>
diff --git a/samples/RenderDemo/Pages/CustomStringAnimator.cs b/samples/RenderDemo/Pages/CustomStringAnimator.cs
index 851a2d0187..398319726e 100644
--- a/samples/RenderDemo/Pages/CustomStringAnimator.cs
+++ b/samples/RenderDemo/Pages/CustomStringAnimator.cs
@@ -1,8 +1,9 @@
-using Avalonia.Animation.Animators;
+using Avalonia.Animation;
+using Avalonia.Animation.Animators;
 
 namespace RenderDemo.Pages
 {
-    public class CustomStringAnimator : Animator<string>
+    public class CustomStringAnimator : CustomAnimatorBase<string>
     {
         public override string Interpolate(double progress, string oldValue, string newValue)
         {
diff --git a/samples/RenderDemo/Pages/Transform3DPage.axaml b/samples/RenderDemo/Pages/Transform3DPage.axaml
index 7f3636648c..36e0be3114 100644
--- a/samples/RenderDemo/Pages/Transform3DPage.axaml
+++ b/samples/RenderDemo/Pages/Transform3DPage.axaml
@@ -134,9 +134,6 @@
     </UserControl.Styles>
 
     <Grid ColumnDefinitions="Auto,*,Auto,*" RowDefinitions="*, Auto, Auto, Auto, Auto, Auto, Auto, Auto">
-        <Grid.Clock>
-            <Clock />
-        </Grid.Clock>
         <Border Name="B1" Background="DarkRed" Classes="Test">
             <Border.RenderTransform>
                 <Rotate3DTransform CenterZ="-100"
diff --git a/samples/RenderDemo/Pages/TransitionsPage.xaml b/samples/RenderDemo/Pages/TransitionsPage.xaml
index 006c2eb20b..6e143f97e4 100644
--- a/samples/RenderDemo/Pages/TransitionsPage.xaml
+++ b/samples/RenderDemo/Pages/TransitionsPage.xaml
@@ -248,12 +248,8 @@
 
   <Grid>
     <StackPanel HorizontalAlignment="Center" VerticalAlignment="Center" ClipToBounds="False">
-      <StackPanel.Clock>
-        <Clock />
-      </StackPanel.Clock>
       <StackPanel Orientation="Horizontal" VerticalAlignment="Center" Spacing="20">
         <TextBlock VerticalAlignment="Center">Hover to activate Transitions.</TextBlock>
-        <Button Content="{Binding PlayStateText}" Command="{Binding TogglePlayState}" Click="ToggleClock" />
       </StackPanel>
       <WrapPanel ClipToBounds="False">
         <Border Classes="Test Rect1" Background="DarkRed"/>
diff --git a/samples/RenderDemo/Pages/TransitionsPage.xaml.cs b/samples/RenderDemo/Pages/TransitionsPage.xaml.cs
index 5f446c9e99..65b33d5ae8 100644
--- a/samples/RenderDemo/Pages/TransitionsPage.xaml.cs
+++ b/samples/RenderDemo/Pages/TransitionsPage.xaml.cs
@@ -18,20 +18,5 @@ namespace RenderDemo.Pages
         {
             AvaloniaXamlLoader.Load(this);
         }
-
-        private void ToggleClock(object sender, RoutedEventArgs args)
-        {
-            var button = sender as Button;
-            var clock = button.Clock;
-
-            if (clock.PlayState == PlayState.Run)
-            {
-                clock.PlayState = PlayState.Pause;
-            }
-            else if (clock.PlayState == PlayState.Pause)
-            {
-                clock.PlayState = PlayState.Run;
-            }
-        }
     }
 }
diff --git a/samples/Sandbox/Sandbox.csproj b/samples/Sandbox/Sandbox.csproj
index d2e66988e0..7a57a13529 100644
--- a/samples/Sandbox/Sandbox.csproj
+++ b/samples/Sandbox/Sandbox.csproj
@@ -5,6 +5,7 @@
     <TargetFramework>net6.0</TargetFramework>
     <TargetLatestRuntimePatch>true</TargetLatestRuntimePatch>
     <IncludeAvaloniaGenerators>true</IncludeAvaloniaGenerators>
+<!--    <AvaloniaXamlIlDebuggerLaunch>true</AvaloniaXamlIlDebuggerLaunch>-->
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/src/Android/Avalonia.Android/AndroidPlatform.cs b/src/Android/Avalonia.Android/AndroidPlatform.cs
index 984d3ed5fc..d5d5f211e9 100644
--- a/src/Android/Avalonia.Android/AndroidPlatform.cs
+++ b/src/Android/Avalonia.Android/AndroidPlatform.cs
@@ -45,7 +45,6 @@ namespace Avalonia.Android
                 .Bind<IPlatformThreadingInterface>().ToConstant(new AndroidThreadingInterface())
                 .Bind<IPlatformIconLoader>().ToSingleton<PlatformIconLoaderStub>()
                 .Bind<IRenderTimer>().ToConstant(new ChoreographerTimer())
-                .Bind<IRenderLoop>().ToConstant(new RenderLoop())
                 .Bind<PlatformHotkeyConfiguration>().ToSingleton<PlatformHotkeyConfiguration>();
 
             if (Options.UseGpu)
@@ -53,11 +52,7 @@ namespace Avalonia.Android
                 EglPlatformGraphics.TryInitialize();
             }
             
-            Compositor = new Compositor(
-                AvaloniaLocator.Current.GetRequiredService<IRenderLoop>(),
-                AvaloniaLocator.Current.GetService<IPlatformGraphics>());
-            
-
+            Compositor = new Compositor(AvaloniaLocator.Current.GetService<IPlatformGraphics>());
         }
     }
 
diff --git a/src/Android/Avalonia.Android/AvaloniaView.cs b/src/Android/Avalonia.Android/AvaloniaView.cs
index 27481a598e..05ec1795f4 100644
--- a/src/Android/Avalonia.Android/AvaloniaView.cs
+++ b/src/Android/Avalonia.Android/AvaloniaView.cs
@@ -67,7 +67,7 @@ namespace Avalonia.Android
                     _timerSubscription = timer.SubscribeView(this);
                 }
 
-                _root.Renderer.Start();
+                _root.StartRendering();
 
                 if (_view.TryGetFeature<IInsetsManager>(out var insetsManager) == true)
                 {
@@ -76,7 +76,7 @@ namespace Avalonia.Android
             }
             else
             {
-                _root.Renderer.Stop();
+                _root.StopRendering();
                 _timerSubscription?.Dispose();
             }
         }
diff --git a/src/Android/Avalonia.Android/Platform/SkiaPlatform/InvalidationAwareSurfaceView.cs b/src/Android/Avalonia.Android/Platform/SkiaPlatform/InvalidationAwareSurfaceView.cs
index 47297a4f76..3fb78591bc 100644
--- a/src/Android/Avalonia.Android/Platform/SkiaPlatform/InvalidationAwareSurfaceView.cs
+++ b/src/Android/Avalonia.Android/Platform/SkiaPlatform/InvalidationAwareSurfaceView.cs
@@ -10,7 +10,7 @@ using Avalonia.Platform;
 
 namespace Avalonia.Android
 {
-    internal abstract class InvalidationAwareSurfaceView : SurfaceView, ISurfaceHolderCallback, IPlatformNativeSurfaceHandle
+    internal abstract class InvalidationAwareSurfaceView : SurfaceView, ISurfaceHolderCallback, INativePlatformHandleSurface
     {
         bool _invalidateQueued;
         readonly object _lock = new object();
diff --git a/src/Android/Avalonia.Android/Platform/SkiaPlatform/TopLevelImpl.cs b/src/Android/Avalonia.Android/Platform/SkiaPlatform/TopLevelImpl.cs
index fae1aacf61..a29f06a106 100644
--- a/src/Android/Avalonia.Android/Platform/SkiaPlatform/TopLevelImpl.cs
+++ b/src/Android/Avalonia.Android/Platform/SkiaPlatform/TopLevelImpl.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Runtime.Versioning;
 using Android.App;
 using Android.Content;
 using Android.Graphics;
@@ -45,6 +46,7 @@ namespace Avalonia.Android.Platform.SkiaPlatform
         private readonly AndroidInsetsManager _insetsManager;
         private readonly ClipboardImpl _clipboard;
         private ViewImpl _view;
+        private WindowTransparencyLevel _transparencyLevel;
 
         public TopLevelImpl(AvaloniaView avaloniaView, bool placeOnTop = false)
         {
@@ -68,6 +70,7 @@ namespace Avalonia.Android.Platform.SkiaPlatform
 
             _nativeControlHost = new AndroidNativeControlHostImpl(avaloniaView);
             _storageProvider = new AndroidStorageProvider((Activity)avaloniaView.Context);
+            _transparencyLevel = WindowTransparencyLevel.None;
 
             _systemNavigationManager = new AndroidSystemNavigationManagerImpl(avaloniaView.Context as IActivityNavigationService);
         }
@@ -103,9 +106,8 @@ namespace Avalonia.Android.Platform.SkiaPlatform
 
         public IEnumerable<object> Surfaces => new object[] { _gl, _framebuffer, Handle };
 
-        public IRenderer CreateRenderer(IRenderRoot root) =>
-            new CompositingRenderer(root, AndroidPlatform.Compositor, () => Surfaces);
-
+        public Compositor Compositor => AndroidPlatform.Compositor;
+        
         public virtual void Hide()
         {
             _view.Visibility = ViewStates.Invisible;
@@ -274,7 +276,18 @@ namespace Avalonia.Android.Platform.SkiaPlatform
         public Action LostFocus { get; set; }
         public Action<WindowTransparencyLevel> TransparencyLevelChanged { get; set; }
 
-        public WindowTransparencyLevel TransparencyLevel { get; private set; }
+        public WindowTransparencyLevel TransparencyLevel 
+        {
+            get => _transparencyLevel;
+            private set
+            {
+                if (_transparencyLevel != value)
+                {
+                    _transparencyLevel = value;
+                    TransparencyLevelChanged?.Invoke(value);
+                }
+            }
+        }
 
         public void SetFrameThemeVariant(PlatformThemeVariant themeVariant)
         {
@@ -299,91 +312,64 @@ namespace Avalonia.Android.Platform.SkiaPlatform
 
         public double Scaling => RenderScaling;
 
-        public void SetTransparencyLevelHint(WindowTransparencyLevel transparencyLevel)
+        public void SetTransparencyLevelHint(IReadOnlyList<WindowTransparencyLevel> transparencyLevels)
         {
-            if (TransparencyLevel != transparencyLevel)
+            if (_view.Context is not AvaloniaMainActivity activity)
+                return;
+
+            foreach (var level in transparencyLevels)
             {
-                bool isBelowR = Build.VERSION.SdkInt < BuildVersionCodes.R;
-                bool isAboveR = Build.VERSION.SdkInt > BuildVersionCodes.R;
-                if (_view.Context is AvaloniaMainActivity activity)
+                if (!IsSupported(level))
+                {
+                    continue;
+                }
+
+                if (level == TransparencyLevel)
+                {
+                    return;
+                }
+
+                if (level == WindowTransparencyLevel.None)
+                {
+                    if (OperatingSystem.IsAndroidVersionAtLeast(30))
+                    {
+                        activity.SetTranslucent(false);
+                    }
+
+                    activity.Window?.SetBackgroundDrawable(new ColorDrawable(Color.White));
+                }
+                else if (level == WindowTransparencyLevel.Transparent)
+                {
+                    if (OperatingSystem.IsAndroidVersionAtLeast(30))
+                    {
+                        activity.SetTranslucent(true);
+                        SetBlurBehind(activity, 0);
+                        activity.Window.SetBackgroundDrawable(new ColorDrawable(Color.Transparent));
+                    }
+                }
+                else if (level == WindowTransparencyLevel.Blur)
                 {
-                    switch (transparencyLevel)
+                    if (OperatingSystem.IsAndroidVersionAtLeast(31))
                     {
-                        case WindowTransparencyLevel.AcrylicBlur:
-                        case WindowTransparencyLevel.ForceAcrylicBlur:
-                        case WindowTransparencyLevel.Mica:
-                        case WindowTransparencyLevel.None:
-                            if (!isBelowR)
-                            {
-                                activity.SetTranslucent(false);
-                            }
-                            if (isAboveR)
-                            {
-                                activity.Window?.ClearFlags(WindowManagerFlags.BlurBehind);
-
-                                var attr = activity.Window?.Attributes;
-                                if (attr != null)
-                                {
-                                    attr.BlurBehindRadius = 0;
-
-                                    activity.Window.Attributes = attr;
-                                }
-                            }
-                            activity.Window.SetBackgroundDrawable(new ColorDrawable(Color.White));
-
-                            if(transparencyLevel != WindowTransparencyLevel.None)
-                            {
-                                return;
-                            }
-                            break;
-                        case WindowTransparencyLevel.Transparent:
-                            if (!isBelowR)
-                            {
-                                activity.SetTranslucent(true);
-                            }
-                            if (isAboveR)
-                            {
-                                activity.Window?.ClearFlags(WindowManagerFlags.BlurBehind);
-
-                                var attr = activity.Window?.Attributes;
-                                if (attr != null)
-                                {
-                                    attr.BlurBehindRadius = 0;
-
-                                    activity.Window.Attributes = attr;
-                                }
-                            }
-                            activity.Window.SetBackgroundDrawable(new ColorDrawable(Color.Transparent));
-                            break;
-                        case WindowTransparencyLevel.Blur:
-                            if (isAboveR)
-                            {
-                                activity.SetTranslucent(true);
-                                activity.Window?.AddFlags(WindowManagerFlags.BlurBehind);
-
-                                var attr = activity.Window?.Attributes;
-                                if (attr != null)
-                                {
-                                    attr.BlurBehindRadius = 120;
-
-                                    activity.Window.Attributes = attr;
-                                }
-                                activity.Window.SetBackgroundDrawable(new ColorDrawable(Color.Transparent));
-                            }
-                            else
-                            {
-                                activity.Window?.ClearFlags(WindowManagerFlags.BlurBehind);
-                                activity.Window.SetBackgroundDrawable(new ColorDrawable(Color.White));
-
-                                return;
-                            }
-                            break;
+                        activity.SetTranslucent(true);
+                        SetBlurBehind(activity, 120);
+                        activity.Window?.SetBackgroundDrawable(new ColorDrawable(Color.Transparent));
                     }
-                    TransparencyLevel = transparencyLevel;
                 }
+
+                TransparencyLevel = level;
+                return;
             }
+
+            // If we get here, we didn't find a supported level. Use the default of None.
+            if (OperatingSystem.IsAndroidVersionAtLeast(30))
+            {
+                activity.SetTranslucent(false);
+            }
+
+            activity.Window?.SetBackgroundDrawable(new ColorDrawable(Color.White));
         }
-        
+
         public virtual object TryGetFeature(Type featureType)
         {
             if (featureType == typeof(IStorageProvider))
@@ -418,6 +404,31 @@ namespace Avalonia.Android.Platform.SkiaPlatform
 
             return null;
         }
+
+        private static bool IsSupported(WindowTransparencyLevel level)
+        {
+            if (level == WindowTransparencyLevel.None)
+                return true;
+            if (level == WindowTransparencyLevel.Transparent)
+                return OperatingSystem.IsAndroidVersionAtLeast(30);
+            if (level == WindowTransparencyLevel.Blur)
+                return OperatingSystem.IsAndroidVersionAtLeast(31);
+            return false;
+        }
+
+        private static void SetBlurBehind(AvaloniaMainActivity activity, int radius)
+        {
+            if (radius == 0)
+                activity.Window?.ClearFlags(WindowManagerFlags.BlurBehind);
+            else
+                activity.Window?.AddFlags(WindowManagerFlags.BlurBehind);
+
+            if (OperatingSystem.IsAndroidVersionAtLeast(31) && activity.Window?.Attributes is { } attr)
+            {
+                attr.BlurBehindRadius = radius;
+                activity.Window.Attributes = attr;
+            }
+        }
     }
 
     internal class AvaloniaInputConnection : BaseInputConnection
diff --git a/src/Avalonia.Base/Animation/Animatable.cs b/src/Avalonia.Base/Animation/Animatable.cs
index 98d4a71415..fb44c10f43 100644
--- a/src/Avalonia.Base/Animation/Animatable.cs
+++ b/src/Avalonia.Base/Animation/Animatable.cs
@@ -17,7 +17,7 @@ namespace Avalonia.Animation
         /// <summary>
         /// Defines the <see cref="Clock"/> property.
         /// </summary>
-        public static readonly StyledProperty<IClock> ClockProperty =
+        internal static readonly StyledProperty<IClock> ClockProperty =
             AvaloniaProperty.Register<Animatable, IClock>(nameof(Clock), inherits: true);
 
         /// <summary>
@@ -36,7 +36,7 @@ namespace Avalonia.Animation
         /// <summary>
         /// Gets or sets the clock which controls the animations on the control.
         /// </summary>
-        public IClock Clock
+        internal IClock Clock
         {
             get => GetValue(ClockProperty);
             set => SetValue(ClockProperty, value);
diff --git a/src/Avalonia.Base/Animation/Animation.cs b/src/Avalonia.Base/Animation/Animation.cs
index dd99c40cd3..4de89bfe97 100644
--- a/src/Avalonia.Base/Animation/Animation.cs
+++ b/src/Avalonia.Base/Animation/Animation.cs
@@ -16,7 +16,7 @@ namespace Avalonia.Animation
     /// <summary>
     /// Tracks the progress of an animation.
     /// </summary>
-    public class Animation : AvaloniaObject, IAnimation
+    public sealed class Animation : AvaloniaObject, IAnimation
     {
         /// <summary>
         /// Defines the <see cref="Duration"/> property.
@@ -186,7 +186,7 @@ namespace Avalonia.Animation
         /// </summary>
         /// <param name="setter">The animation setter.</param>
         /// <returns>The property animator type.</returns>
-        public static (Type Type, Func<IAnimator> Factory)? GetAnimator(IAnimationSetter setter)
+        internal static (Type Type, Func<IAnimator> Factory)? GetAnimator(IAnimationSetter setter)
         {
             if (s_animators.TryGetValue(setter, out var type))
             {
@@ -200,11 +200,9 @@ namespace Avalonia.Animation
         /// </summary>
         /// <param name="setter">The animation setter.</param>
         /// <param name="value">The property animator value.</param>
-        public static void SetAnimator(IAnimationSetter setter,
-            [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicParameterlessConstructor | DynamicallyAccessedMemberTypes.PublicMethods)]
-            Type value)
+        public static void SetAnimator(IAnimationSetter setter, CustomAnimatorBase value)
         {
-            s_animators[setter] = (value, () => (IAnimator)Activator.CreateInstance(value)!);
+            s_animators[setter] = (value.WrapperType, value.CreateWrapper);
         }
 
         private readonly static List<(Func<AvaloniaProperty, bool> Condition, Type Animator, Func<IAnimator> Factory)> Animators = new()
@@ -233,7 +231,7 @@ namespace Avalonia.Animation
         /// <typeparam name="TAnimator">
         /// The type of the animator to instantiate.
         /// </typeparam>
-        public static void RegisterAnimator<TAnimator>(Func<AvaloniaProperty, bool> condition)
+        internal static void RegisterAnimator<TAnimator>(Func<AvaloniaProperty, bool> condition)
             where TAnimator : IAnimator, new()
         {
             Animators.Insert(0, (condition, typeof(TAnimator), () => new TAnimator()));
@@ -312,8 +310,11 @@ namespace Avalonia.Animation
             return (newAnimatorInstances, subscriptions);
         }
 
+        IDisposable IAnimation.Apply(Animatable control, IClock? clock, IObservable<bool> match, Action? onComplete)
+            => Apply(control, clock, match, onComplete);
+        
         /// <inheritdoc/>
-        public IDisposable Apply(Animatable control, IClock? clock, IObservable<bool> match, Action? onComplete)
+        internal IDisposable Apply(Animatable control, IClock? clock, IObservable<bool> match, Action? onComplete)
         {
             var (animators, subscriptions) = InterpretKeyframes(control);
             if (animators.Count == 1)
@@ -358,14 +359,20 @@ namespace Avalonia.Animation
             return new CompositeDisposable(subscriptions);
         }
 
+        public Task RunAsync(Animatable control, CancellationToken cancellationToken = default) =>
+            RunAsync(control, null, cancellationToken);
+        
         /// <inheritdoc/>
-        public Task RunAsync(Animatable control, IClock? clock = null)
+        internal Task RunAsync(Animatable control, IClock? clock)
         {
             return RunAsync(control, clock, default);
         }
 
+        Task IAnimation.RunAsync(Animatable control, IClock? clock, CancellationToken cancellationToken)
+            => RunAsync(control, clock, cancellationToken);
+        
         /// <inheritdoc/>
-        public Task RunAsync(Animatable control, IClock? clock = null, CancellationToken cancellationToken = default)
+        internal Task RunAsync(Animatable control, IClock? clock, CancellationToken cancellationToken)
         {
             if (cancellationToken.IsCancellationRequested)
             {
diff --git a/src/Avalonia.Base/Animation/AnimatorDrivenTransition.cs b/src/Avalonia.Base/Animation/AnimatorDrivenTransition.cs
index 88c8ec5ec1..b417c952fb 100644
--- a/src/Avalonia.Base/Animation/AnimatorDrivenTransition.cs
+++ b/src/Avalonia.Base/Animation/AnimatorDrivenTransition.cs
@@ -1,5 +1,6 @@
 using System;
 using Avalonia.Animation.Animators;
+using Avalonia.Animation.Easings;
 
 namespace Avalonia.Animation
 {
@@ -8,13 +9,11 @@ namespace Avalonia.Animation
     /// </summary>
     /// <typeparam name="T">Type of the transitioned value.</typeparam>
     /// <typeparam name="TAnimator">Type of the animator.</typeparam>
-    public abstract class AnimatorDrivenTransition<T, TAnimator> : Transition<T> where TAnimator : Animator<T>, new()
+    internal static class AnimatorDrivenTransition<T, TAnimator> where TAnimator : Animator<T>, new()
     {
         private static readonly TAnimator s_animator = new TAnimator();
 
-        public override IObservable<T> DoTransition(IObservable<double> progress, T oldValue, T newValue)
-        {
-            return new AnimatorTransitionObservable<T, TAnimator>(s_animator, progress, Easing, oldValue, newValue);
-        }
+        public static IObservable<T> Transition(IEasing easing, IObservable<double> progress, T oldValue, T newValue) =>
+            new AnimatorTransitionObservable<T, TAnimator>(s_animator, progress, easing, oldValue, newValue);
     }
 }
diff --git a/src/Avalonia.Base/Animation/AnimatorKeyFrame.cs b/src/Avalonia.Base/Animation/AnimatorKeyFrame.cs
index 892be5cb26..81f742de9a 100644
--- a/src/Avalonia.Base/Animation/AnimatorKeyFrame.cs
+++ b/src/Avalonia.Base/Animation/AnimatorKeyFrame.cs
@@ -11,7 +11,7 @@ namespace Avalonia.Animation
     /// Defines a KeyFrame that is used for
     /// <see cref="Animator{T}"/> objects.
     /// </summary>
-    public class AnimatorKeyFrame : AvaloniaObject
+    internal class AnimatorKeyFrame : AvaloniaObject
     {
         public static readonly DirectProperty<AnimatorKeyFrame, object?> ValueProperty =
             AvaloniaProperty.RegisterDirect<AnimatorKeyFrame, object?>(nameof(Value), k => k.Value, (k, v) => k.Value = v);
diff --git a/src/Avalonia.Base/Animation/AnimatorTransitionObservable.cs b/src/Avalonia.Base/Animation/AnimatorTransitionObservable.cs
index 3cc185179b..7da764b475 100644
--- a/src/Avalonia.Base/Animation/AnimatorTransitionObservable.cs
+++ b/src/Avalonia.Base/Animation/AnimatorTransitionObservable.cs
@@ -9,17 +9,15 @@ namespace Avalonia.Animation
     /// </summary>
     /// <typeparam name="T">Type of the transitioned value.</typeparam>
     /// <typeparam name="TAnimator">Type of the animator.</typeparam>
-    public class AnimatorTransitionObservable<T, TAnimator> : TransitionObservableBase<T> where TAnimator : Animator<T>
+    internal class AnimatorTransitionObservable<T, TAnimator> : TransitionObservableBase<T> where TAnimator : Animator<T>
     {
         private readonly TAnimator _animator;
-        private readonly Easing _easing;
         private readonly T _oldValue;
         private readonly T _newValue;
 
-        public AnimatorTransitionObservable(TAnimator animator, IObservable<double> progress, Easing easing, T oldValue, T newValue) : base(progress, easing)
+        public AnimatorTransitionObservable(TAnimator animator, IObservable<double> progress, IEasing easing, T oldValue, T newValue) : base(progress, easing)
         {
             _animator = animator;
-            _easing = easing;
             _oldValue = oldValue;
             _newValue = newValue;
         }
diff --git a/src/Avalonia.Base/Animation/Animators/Animator`1.cs b/src/Avalonia.Base/Animation/Animators/Animator`1.cs
index 2db890bd0a..f93067d642 100644
--- a/src/Avalonia.Base/Animation/Animators/Animator`1.cs
+++ b/src/Avalonia.Base/Animation/Animators/Animator`1.cs
@@ -11,7 +11,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Base class for <see cref="Animator{T}"/> objects
     /// </summary>
-    public abstract class Animator<T> : AvaloniaList<AnimatorKeyFrame>, IAnimator
+    internal abstract class Animator<T> : AvaloniaList<AnimatorKeyFrame>, IAnimator
     {
         /// <summary>
         /// List of type-converted keyframes.
diff --git a/src/Avalonia.Base/Animation/Animators/BaseBrushAnimator.cs b/src/Avalonia.Base/Animation/Animators/BaseBrushAnimator.cs
index 07c147ef6d..96617b1732 100644
--- a/src/Avalonia.Base/Animation/Animators/BaseBrushAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/BaseBrushAnimator.cs
@@ -15,7 +15,7 @@ namespace Avalonia.Animation.Animators
     /// redirect them to the properly registered
     /// animators in this class.
     /// </summary>
-    public class BaseBrushAnimator : Animator<IBrush?>
+    internal class BaseBrushAnimator : Animator<IBrush?>
     {
         private static readonly List<(Func<Type, bool> Match, Type AnimatorType, Func<IAnimator> AnimatorFactory)> _brushAnimators = new();
 
diff --git a/src/Avalonia.Base/Animation/Animators/BoolAnimator.cs b/src/Avalonia.Base/Animation/Animators/BoolAnimator.cs
index f02fd8dfaa..7c79a53cc5 100644
--- a/src/Avalonia.Base/Animation/Animators/BoolAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/BoolAnimator.cs
@@ -3,7 +3,7 @@
     /// <summary>
     /// Animator that handles <see cref="bool"/> properties.
     /// </summary>
-    public class BoolAnimator : Animator<bool>
+    internal class BoolAnimator : Animator<bool>
     {
         /// <inheritdocs/>
         public override bool Interpolate(double progress, bool oldValue, bool newValue)
diff --git a/src/Avalonia.Base/Animation/Animators/BoxShadowAnimator.cs b/src/Avalonia.Base/Animation/Animators/BoxShadowAnimator.cs
index ff76902425..08ed3cef4a 100644
--- a/src/Avalonia.Base/Animation/Animators/BoxShadowAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/BoxShadowAnimator.cs
@@ -2,7 +2,7 @@ using Avalonia.Media;
 
 namespace Avalonia.Animation.Animators
 {
-    public class BoxShadowAnimator : Animator<BoxShadow>
+    internal class BoxShadowAnimator : Animator<BoxShadow>
     {
         static ColorAnimator s_colorAnimator = new ColorAnimator();
         static DoubleAnimator s_doubleAnimator = new DoubleAnimator();
diff --git a/src/Avalonia.Base/Animation/Animators/BoxShadowsAnimator.cs b/src/Avalonia.Base/Animation/Animators/BoxShadowsAnimator.cs
index c6f96a2d0e..f1d12bfd65 100644
--- a/src/Avalonia.Base/Animation/Animators/BoxShadowsAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/BoxShadowsAnimator.cs
@@ -2,7 +2,7 @@ using Avalonia.Media;
 
 namespace Avalonia.Animation.Animators
 {
-    public class BoxShadowsAnimator :  Animator<BoxShadows>
+    internal class BoxShadowsAnimator : Animator<BoxShadows>
     {
         private static readonly BoxShadowAnimator s_boxShadowAnimator = new BoxShadowAnimator();
         public override BoxShadows Interpolate(double progress, BoxShadows oldValue, BoxShadows newValue)
diff --git a/src/Avalonia.Base/Animation/Animators/ByteAnimator.cs b/src/Avalonia.Base/Animation/Animators/ByteAnimator.cs
index 9fce07895c..337ef9ecff 100644
--- a/src/Avalonia.Base/Animation/Animators/ByteAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/ByteAnimator.cs
@@ -5,7 +5,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="byte"/> properties.
     /// </summary>
-    public class ByteAnimator : Animator<byte>
+    internal class ByteAnimator : Animator<byte>
     {
         const double maxVal = (double)byte.MaxValue;
 
diff --git a/src/Avalonia.Base/Animation/Animators/ColorAnimator.cs b/src/Avalonia.Base/Animation/Animators/ColorAnimator.cs
index 7be974b9e5..719d0d67ab 100644
--- a/src/Avalonia.Base/Animation/Animators/ColorAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/ColorAnimator.cs
@@ -12,7 +12,7 @@ namespace Avalonia.Animation.Animators
     /// Animator that interpolates <see cref="Color"/> through 
     /// gamma sRGB color space for better visual result.
     /// </summary>
-    public class ColorAnimator : Animator<Color>
+    internal class ColorAnimator : Animator<Color>
     {
         /// <summary>
         /// Opto-electronic conversion function for the sRGB color space.
diff --git a/src/Avalonia.Base/Animation/Animators/CornerRadiusAnimator.cs b/src/Avalonia.Base/Animation/Animators/CornerRadiusAnimator.cs
index 8129bd38de..bf52ef0caf 100644
--- a/src/Avalonia.Base/Animation/Animators/CornerRadiusAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/CornerRadiusAnimator.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="CornerRadius"/> properties.
     /// </summary>
-    public class CornerRadiusAnimator : Animator<CornerRadius>
+    internal class CornerRadiusAnimator : Animator<CornerRadius>
     {
         public override CornerRadius Interpolate(double progress, CornerRadius oldValue, CornerRadius newValue)
         {
diff --git a/src/Avalonia.Base/Animation/Animators/DecimalAnimator.cs b/src/Avalonia.Base/Animation/Animators/DecimalAnimator.cs
index 5aed5e5f3d..8c737ca647 100644
--- a/src/Avalonia.Base/Animation/Animators/DecimalAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/DecimalAnimator.cs
@@ -3,7 +3,7 @@
     /// <summary>
     /// Animator that handles <see cref="decimal"/> properties.
     /// </summary>
-    public class DecimalAnimator : Animator<decimal>
+    internal class DecimalAnimator : Animator<decimal>
     {
         /// <inheritdocs/>
         public override decimal Interpolate(double progress, decimal oldValue, decimal newValue)
diff --git a/src/Avalonia.Base/Animation/Animators/DoubleAnimator.cs b/src/Avalonia.Base/Animation/Animators/DoubleAnimator.cs
index 1ca3fabc47..af44bcc9b4 100644
--- a/src/Avalonia.Base/Animation/Animators/DoubleAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/DoubleAnimator.cs
@@ -3,7 +3,7 @@
     /// <summary>
     /// Animator that handles <see cref="double"/> properties.
     /// </summary>
-    public class DoubleAnimator : Animator<double>
+    internal class DoubleAnimator : Animator<double>
     {
         /// <inheritdocs/>
         public override double Interpolate(double progress, double oldValue, double newValue)
diff --git a/src/Avalonia.Base/Animation/Animators/FloatAnimator.cs b/src/Avalonia.Base/Animation/Animators/FloatAnimator.cs
index 62f48a15a3..608f421da5 100644
--- a/src/Avalonia.Base/Animation/Animators/FloatAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/FloatAnimator.cs
@@ -3,7 +3,7 @@
     /// <summary>
     /// Animator that handles <see cref="float"/> properties.
     /// </summary>
-    public class FloatAnimator : Animator<float>
+    internal class FloatAnimator : Animator<float>
     {
         /// <inheritdocs/>
         public override float Interpolate(double progress, float oldValue, float newValue)
diff --git a/src/Avalonia.Base/Animation/Animators/GradientBrushAnimator.cs b/src/Avalonia.Base/Animation/Animators/GradientBrushAnimator.cs
index 801f247754..9cde01f90c 100644
--- a/src/Avalonia.Base/Animation/Animators/GradientBrushAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/GradientBrushAnimator.cs
@@ -13,7 +13,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="SolidColorBrush"/> values. 
     /// </summary>
-    public class GradientBrushAnimator : Animator<IGradientBrush?>
+    internal class GradientBrushAnimator : Animator<IGradientBrush?>
     {
         private static readonly RelativePointAnimator s_relativePointAnimator = new RelativePointAnimator();
         private static readonly DoubleAnimator s_doubleAnimator = new DoubleAnimator();
diff --git a/src/Avalonia.Base/Animation/Animators/Int16Animator.cs b/src/Avalonia.Base/Animation/Animators/Int16Animator.cs
index 5235082fc4..4bd9aa3e84 100644
--- a/src/Avalonia.Base/Animation/Animators/Int16Animator.cs
+++ b/src/Avalonia.Base/Animation/Animators/Int16Animator.cs
@@ -5,7 +5,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="Int16"/> properties.
     /// </summary>
-    public class Int16Animator : Animator<Int16>
+    internal class Int16Animator : Animator<Int16>
     {
         const double maxVal = (double)Int16.MaxValue;
 
diff --git a/src/Avalonia.Base/Animation/Animators/Int32Animator.cs b/src/Avalonia.Base/Animation/Animators/Int32Animator.cs
index 2596f13e84..96c682b18e 100644
--- a/src/Avalonia.Base/Animation/Animators/Int32Animator.cs
+++ b/src/Avalonia.Base/Animation/Animators/Int32Animator.cs
@@ -5,7 +5,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="Int32"/> properties.
     /// </summary>
-    public class Int32Animator : Animator<Int32>
+    internal class Int32Animator : Animator<Int32>
     {
         const double maxVal = (double)Int32.MaxValue;
 
diff --git a/src/Avalonia.Base/Animation/Animators/Int64Animator.cs b/src/Avalonia.Base/Animation/Animators/Int64Animator.cs
index d05750d35c..1db357d64d 100644
--- a/src/Avalonia.Base/Animation/Animators/Int64Animator.cs
+++ b/src/Avalonia.Base/Animation/Animators/Int64Animator.cs
@@ -5,7 +5,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="Int64"/> properties.
     /// </summary>
-    public class Int64Animator : Animator<Int64>
+    internal class Int64Animator : Animator<Int64>
     {
         const double maxVal = (double)Int64.MaxValue;
 
diff --git a/src/Avalonia.Base/Animation/Animators/PointAnimator.cs b/src/Avalonia.Base/Animation/Animators/PointAnimator.cs
index 793691e5ac..8e85abda8a 100644
--- a/src/Avalonia.Base/Animation/Animators/PointAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/PointAnimator.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="Point"/> properties.
     /// </summary>
-    public class PointAnimator : Animator<Point>
+    internal class PointAnimator : Animator<Point>
     {
         public override Point Interpolate(double progress, Point oldValue, Point newValue)
         { 
diff --git a/src/Avalonia.Base/Animation/Animators/RectAnimator.cs b/src/Avalonia.Base/Animation/Animators/RectAnimator.cs
index b2d3ec2996..3b73f3cf82 100644
--- a/src/Avalonia.Base/Animation/Animators/RectAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/RectAnimator.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="Rect"/> properties.
     /// </summary>
-    public class RectAnimator : Animator<Rect>
+    internal class RectAnimator : Animator<Rect>
     {
         public override Rect Interpolate(double progress, Rect oldValue, Rect newValue)
         {
diff --git a/src/Avalonia.Base/Animation/Animators/RelativePointAnimator.cs b/src/Avalonia.Base/Animation/Animators/RelativePointAnimator.cs
index 348a2e4a35..ab49dcd95a 100644
--- a/src/Avalonia.Base/Animation/Animators/RelativePointAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/RelativePointAnimator.cs
@@ -3,7 +3,7 @@
     /// <summary>
     /// Animator that handles <see cref="RelativePoint"/> properties.
     /// </summary>
-    public class RelativePointAnimator : Animator<RelativePoint>
+    internal class RelativePointAnimator : Animator<RelativePoint>
     {
         private static readonly PointAnimator s_pointAnimator = new PointAnimator();
 
diff --git a/src/Avalonia.Base/Animation/Animators/SizeAnimator.cs b/src/Avalonia.Base/Animation/Animators/SizeAnimator.cs
index bb4f343e4a..50f46c9b15 100644
--- a/src/Avalonia.Base/Animation/Animators/SizeAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/SizeAnimator.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="Size"/> properties.
     /// </summary>
-    public class SizeAnimator : Animator<Size>
+    internal class SizeAnimator : Animator<Size>
     {
         public override Size Interpolate(double progress, Size oldValue, Size newValue)
         {
diff --git a/src/Avalonia.Base/Animation/Animators/SolidColorBrushAnimator.cs b/src/Avalonia.Base/Animation/Animators/SolidColorBrushAnimator.cs
index 9256c7be5e..ddeb3637b9 100644
--- a/src/Avalonia.Base/Animation/Animators/SolidColorBrushAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/SolidColorBrushAnimator.cs
@@ -10,7 +10,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="SolidColorBrush"/> values. 
     /// </summary>
-    public class ISolidColorBrushAnimator : Animator<ISolidColorBrush?>
+    internal class ISolidColorBrushAnimator : Animator<ISolidColorBrush?>
     {
         private static readonly DoubleAnimator s_doubleAnimator = new DoubleAnimator();
 
diff --git a/src/Avalonia.Base/Animation/Animators/ThicknessAnimator.cs b/src/Avalonia.Base/Animation/Animators/ThicknessAnimator.cs
index a6ae95ce3f..0dd497329c 100644
--- a/src/Avalonia.Base/Animation/Animators/ThicknessAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/ThicknessAnimator.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="Thickness"/> properties.
     /// </summary>
-    public class ThicknessAnimator : Animator<Thickness>
+    internal class ThicknessAnimator : Animator<Thickness>
     {
         public override Thickness Interpolate(double progress, Thickness oldValue, Thickness newValue)
         {
diff --git a/src/Avalonia.Base/Animation/Animators/TransformAnimator.cs b/src/Avalonia.Base/Animation/Animators/TransformAnimator.cs
index 8040fb595b..c6155837ec 100644
--- a/src/Avalonia.Base/Animation/Animators/TransformAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/TransformAnimator.cs
@@ -9,7 +9,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="Transform"/> properties.
     /// </summary>
-    public class TransformAnimator : Animator<double>
+    internal class TransformAnimator : Animator<double>
     {
         DoubleAnimator? _doubleAnimator;
 
diff --git a/src/Avalonia.Base/Animation/Animators/TransformOperationsAnimator.cs b/src/Avalonia.Base/Animation/Animators/TransformOperationsAnimator.cs
index 8e9d20eb8f..bf88da04c1 100644
--- a/src/Avalonia.Base/Animation/Animators/TransformOperationsAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/TransformOperationsAnimator.cs
@@ -4,7 +4,7 @@ using Avalonia.Media.Transformation;
 
 namespace Avalonia.Animation.Animators
 {
-    public class TransformOperationsAnimator : Animator<TransformOperations>
+    internal class TransformOperationsAnimator : Animator<TransformOperations>
     {
         public TransformOperationsAnimator()
         {
diff --git a/src/Avalonia.Base/Animation/Animators/UInt16Animator.cs b/src/Avalonia.Base/Animation/Animators/UInt16Animator.cs
index 6c9588a966..d0d208827f 100644
--- a/src/Avalonia.Base/Animation/Animators/UInt16Animator.cs
+++ b/src/Avalonia.Base/Animation/Animators/UInt16Animator.cs
@@ -5,7 +5,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="UInt16"/> properties.
     /// </summary>
-    public class UInt16Animator : Animator<UInt16>
+    internal class UInt16Animator : Animator<UInt16>
     {
         const double maxVal = (double)UInt16.MaxValue;
 
diff --git a/src/Avalonia.Base/Animation/Animators/UInt32Animator.cs b/src/Avalonia.Base/Animation/Animators/UInt32Animator.cs
index e2af533566..35fff24cb6 100644
--- a/src/Avalonia.Base/Animation/Animators/UInt32Animator.cs
+++ b/src/Avalonia.Base/Animation/Animators/UInt32Animator.cs
@@ -5,7 +5,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="UInt32"/> properties.
     /// </summary>
-    public class UInt32Animator : Animator<UInt32>
+    internal class UInt32Animator : Animator<UInt32>
     {
         const double maxVal = (double)UInt32.MaxValue;
 
diff --git a/src/Avalonia.Base/Animation/Animators/UInt64Animator.cs b/src/Avalonia.Base/Animation/Animators/UInt64Animator.cs
index a709a77100..cb3211c822 100644
--- a/src/Avalonia.Base/Animation/Animators/UInt64Animator.cs
+++ b/src/Avalonia.Base/Animation/Animators/UInt64Animator.cs
@@ -5,7 +5,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="UInt64"/> properties.
     /// </summary>
-    public class UInt64Animator : Animator<UInt64>
+    internal class UInt64Animator : Animator<UInt64>
     {
         const double maxVal = (double)UInt64.MaxValue;
 
diff --git a/src/Avalonia.Base/Animation/Animators/VectorAnimator.cs b/src/Avalonia.Base/Animation/Animators/VectorAnimator.cs
index e1ffb60971..90cdf017fd 100644
--- a/src/Avalonia.Base/Animation/Animators/VectorAnimator.cs
+++ b/src/Avalonia.Base/Animation/Animators/VectorAnimator.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Animation.Animators
     /// <summary>
     /// Animator that handles <see cref="Vector"/> properties.
     /// </summary>
-    public class VectorAnimator : Animator<Vector>
+    internal class VectorAnimator : Animator<Vector>
     {
         public override Vector Interpolate(double progress, Vector oldValue, Vector newValue)
         {
diff --git a/src/Avalonia.Base/Animation/Clock.cs b/src/Avalonia.Base/Animation/Clock.cs
index f2bce9d3a5..10282f2b79 100644
--- a/src/Avalonia.Base/Animation/Clock.cs
+++ b/src/Avalonia.Base/Animation/Clock.cs
@@ -3,7 +3,10 @@ using Avalonia.Reactive;
 
 namespace Avalonia.Animation
 {
-    public class Clock : ClockBase
+    // Note: this class was always broken: it subscribes to the global clock immediately even it if
+    // doesn't actually have subscriptions
+    
+    internal class Clock : ClockBase
     {
         public static IClock GlobalClock => AvaloniaLocator.Current.GetRequiredService<IGlobalClock>();
 
diff --git a/src/Avalonia.Base/Animation/ClockBase.cs b/src/Avalonia.Base/Animation/ClockBase.cs
index c6e5a363be..f8b79f650d 100644
--- a/src/Avalonia.Base/Animation/ClockBase.cs
+++ b/src/Avalonia.Base/Animation/ClockBase.cs
@@ -3,7 +3,7 @@ using Avalonia.Reactive;
 
 namespace Avalonia.Animation
 {
-    public class ClockBase : IClock
+    internal class ClockBase : IClock
     {
         private readonly ClockObservable _observable;
 
diff --git a/src/Avalonia.Base/Animation/Easings/IEasing.cs b/src/Avalonia.Base/Animation/Easings/IEasing.cs
index 9c9c7b3a99..804c7b7912 100644
--- a/src/Avalonia.Base/Animation/Easings/IEasing.cs
+++ b/src/Avalonia.Base/Animation/Easings/IEasing.cs
@@ -1,8 +1,11 @@
+using Avalonia.Metadata;
+
 namespace Avalonia.Animation.Easings
 {
     /// <summary>
     /// Defines the interface for easing classes.
     /// </summary>
+    [NotClientImplementable]
     public interface IEasing
     {
         /// <summary>
diff --git a/src/Avalonia.Base/Animation/Easings/SpringEasing.cs b/src/Avalonia.Base/Animation/Easings/SpringEasing.cs
index 70e74c639f..c850498495 100644
--- a/src/Avalonia.Base/Animation/Easings/SpringEasing.cs
+++ b/src/Avalonia.Base/Animation/Easings/SpringEasing.cs
@@ -64,11 +64,6 @@ public class SpringEasing : Easing
         Damping = damping;
         InitialVelocity = initialVelocity;
     }
-
-    public SpringEasing(Spring keySpline)
-    {
-        _internalSpring = keySpline;
-    }
     
     public SpringEasing()
     {
diff --git a/src/Avalonia.Base/Animation/IAnimation.cs b/src/Avalonia.Base/Animation/IAnimation.cs
index eda86ed106..a5b8b75b12 100644
--- a/src/Avalonia.Base/Animation/IAnimation.cs
+++ b/src/Avalonia.Base/Animation/IAnimation.cs
@@ -14,11 +14,11 @@ namespace Avalonia.Animation
         /// <summary>
         /// Apply the animation to the specified control and run it when <paramref name="match" /> produces <c>true</c>.
         /// </summary>
-        IDisposable Apply(Animatable control, IClock? clock, IObservable<bool> match, Action? onComplete = null);
+        internal IDisposable Apply(Animatable control, IClock? clock, IObservable<bool> match, Action? onComplete = null);
 
         /// <summary>
         /// Run the animation on the specified control.
         /// </summary>
-        Task RunAsync(Animatable control, IClock clock, CancellationToken cancellationToken = default);
+        internal Task RunAsync(Animatable control, IClock clock, CancellationToken cancellationToken = default);
     }
 }
diff --git a/src/Avalonia.Base/Animation/IAnimationSetter.cs b/src/Avalonia.Base/Animation/IAnimationSetter.cs
index 8c4ba95517..2925f1e0b9 100644
--- a/src/Avalonia.Base/Animation/IAnimationSetter.cs
+++ b/src/Avalonia.Base/Animation/IAnimationSetter.cs
@@ -2,7 +2,7 @@ using Avalonia.Metadata;
 
 namespace Avalonia.Animation
 {
-    [NotClientImplementable]
+    [NotClientImplementable, PrivateApi]
     public interface IAnimationSetter
     {
         AvaloniaProperty? Property { get; set; }
diff --git a/src/Avalonia.Base/Animation/IAnimator.cs b/src/Avalonia.Base/Animation/IAnimator.cs
index 06ba8dc329..9fed7be9be 100644
--- a/src/Avalonia.Base/Animation/IAnimator.cs
+++ b/src/Avalonia.Base/Animation/IAnimator.cs
@@ -7,8 +7,7 @@ namespace Avalonia.Animation
     /// <summary>
     /// Interface for Animator objects
     /// </summary>
-    [NotClientImplementable]
-    public interface IAnimator : IList<AnimatorKeyFrame>
+    internal interface IAnimator : IList<AnimatorKeyFrame>
     {
         /// <summary>
         /// The target property.
diff --git a/src/Avalonia.Base/Animation/IClock.cs b/src/Avalonia.Base/Animation/IClock.cs
index 7b3b7b3924..78e5c38103 100644
--- a/src/Avalonia.Base/Animation/IClock.cs
+++ b/src/Avalonia.Base/Animation/IClock.cs
@@ -3,8 +3,7 @@ using Avalonia.Metadata;
 
 namespace Avalonia.Animation
 {
-    [NotClientImplementable]
-    public interface IClock : IObservable<TimeSpan>
+    internal interface IClock : IObservable<TimeSpan>
     {
         PlayState PlayState { get; set; }
     }
diff --git a/src/Avalonia.Base/Animation/ICustomAnimator.cs b/src/Avalonia.Base/Animation/ICustomAnimator.cs
new file mode 100644
index 0000000000..88c9974ca6
--- /dev/null
+++ b/src/Avalonia.Base/Animation/ICustomAnimator.cs
@@ -0,0 +1,30 @@
+using System;
+using Avalonia.Animation.Animators;
+
+namespace Avalonia.Animation;
+
+public abstract class CustomAnimatorBase
+{
+    internal abstract IAnimator CreateWrapper();
+    internal abstract Type WrapperType { get; }
+}
+
+public abstract class CustomAnimatorBase<T> : CustomAnimatorBase
+{
+    public abstract T Interpolate(double progress, T oldValue, T newValue);
+
+    internal override Type WrapperType => typeof(AnimatorWrapper);
+    internal override IAnimator CreateWrapper() => new AnimatorWrapper(this);
+
+    internal class AnimatorWrapper : Animator<T>
+    {
+        private readonly CustomAnimatorBase<T> _parent;
+
+        public AnimatorWrapper(CustomAnimatorBase<T> parent)
+        {
+            _parent = parent;
+        }
+        
+        public override T Interpolate(double progress, T oldValue, T newValue) => _parent.Interpolate(progress, oldValue, newValue);
+    }
+}
\ No newline at end of file
diff --git a/src/Avalonia.Base/Animation/IGlobalClock.cs b/src/Avalonia.Base/Animation/IGlobalClock.cs
index 138dc07539..9b9516aa91 100644
--- a/src/Avalonia.Base/Animation/IGlobalClock.cs
+++ b/src/Avalonia.Base/Animation/IGlobalClock.cs
@@ -2,8 +2,7 @@ using Avalonia.Metadata;
 
 namespace Avalonia.Animation
 {
-    [NotClientImplementable]
-    public interface IGlobalClock : IClock
+    internal interface IGlobalClock : IClock
     {
     }
 }
diff --git a/src/Avalonia.Base/Animation/ITransition.cs b/src/Avalonia.Base/Animation/ITransition.cs
index 639b92ce35..622b30eea4 100644
--- a/src/Avalonia.Base/Animation/ITransition.cs
+++ b/src/Avalonia.Base/Animation/ITransition.cs
@@ -6,13 +6,13 @@ namespace Avalonia.Animation
     /// <summary>
     /// Interface for Transition objects.
     /// </summary>
-    [NotClientImplementable]
+    [NotClientImplementable, PrivateApi]
     public interface ITransition
     {
         /// <summary>
         /// Applies the transition to the specified <see cref="Animatable"/>.
         /// </summary>
-        IDisposable Apply(Animatable control, IClock clock, object? oldValue, object? newValue);
+        internal IDisposable Apply(Animatable control, IClock clock, object? oldValue, object? newValue);
 
         /// <summary>
         /// Gets the property to be animated.
diff --git a/src/Avalonia.Base/Animation/KeyFrame.cs b/src/Avalonia.Base/Animation/KeyFrame.cs
index 3ab7a70d90..9188167d0e 100644
--- a/src/Avalonia.Base/Animation/KeyFrame.cs
+++ b/src/Avalonia.Base/Animation/KeyFrame.cs
@@ -15,7 +15,7 @@ namespace Avalonia.Animation
     /// Stores data regarding a specific key
     /// point and value in an animation.
     /// </summary>
-    public class KeyFrame : AvaloniaObject
+    public sealed class KeyFrame : AvaloniaObject
     {
         private TimeSpan _ktimeSpan;
         private Cue _kCue;
diff --git a/src/Avalonia.Base/Animation/KeyFrames.cs b/src/Avalonia.Base/Animation/KeyFrames.cs
index 2e9efa8691..654526741e 100644
--- a/src/Avalonia.Base/Animation/KeyFrames.cs
+++ b/src/Avalonia.Base/Animation/KeyFrames.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Animation
     /// <summary>
     /// A collection of <see cref="KeyFrame"/>s.
     /// </summary>
-    public class KeyFrames : AvaloniaList<KeyFrame>
+    public sealed class KeyFrames : AvaloniaList<KeyFrame>
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="KeyFrames"/> class.
diff --git a/src/Avalonia.Base/Animation/KeySpline.cs b/src/Avalonia.Base/Animation/KeySpline.cs
index ed6adb79b8..218a7599d5 100644
--- a/src/Avalonia.Base/Animation/KeySpline.cs
+++ b/src/Avalonia.Base/Animation/KeySpline.cs
@@ -17,7 +17,7 @@ namespace Avalonia.Animation
     /// See https://docs.microsoft.com/en-us/dotnet/api/system.windows.media.animation.keyspline
     /// </summary>
     [TypeConverter(typeof(KeySplineTypeConverter))]
-    public class KeySpline : AvaloniaObject
+    public sealed class KeySpline : AvaloniaObject
     {
         // Control points
         private double _controlPointX1;
diff --git a/src/Avalonia.Base/Animation/RenderLoopClock.cs b/src/Avalonia.Base/Animation/RenderLoopClock.cs
deleted file mode 100644
index de86b5fee2..0000000000
--- a/src/Avalonia.Base/Animation/RenderLoopClock.cs
+++ /dev/null
@@ -1,26 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Text;
-using Avalonia.Rendering;
-
-namespace Avalonia.Animation
-{
-    public class RenderLoopClock : ClockBase, IRenderLoopTask, IGlobalClock
-    {
-        protected override void Stop()
-        {
-            AvaloniaLocator.Current.GetRequiredService<IRenderLoop>().Remove(this);
-        }
-
-        bool IRenderLoopTask.NeedsUpdate => HasSubscriptions;
-
-        void IRenderLoopTask.Render()
-        {
-        }
-
-        void IRenderLoopTask.Update(TimeSpan time)
-        {
-            Pulse(time);
-        }
-    }
-}
diff --git a/src/Avalonia.Base/Animation/Spring.cs b/src/Avalonia.Base/Animation/Spring.cs
index 03ada9196d..3117a9c18a 100644
--- a/src/Avalonia.Base/Animation/Spring.cs
+++ b/src/Avalonia.Base/Animation/Spring.cs
@@ -10,7 +10,7 @@ namespace Avalonia.Animation;
 /// Determines how an animation is used based on spring formula.
 /// </summary>
 [TypeConverter(typeof(SpringTypeConverter))]
-public class Spring
+internal class Spring
 {
     private SpringSolver _springSolver;
     private double _mass;
diff --git a/src/Avalonia.Base/Animation/SpringTypeConverter.cs b/src/Avalonia.Base/Animation/SpringTypeConverter.cs
index cfcf4c4a14..95903c74e4 100644
--- a/src/Avalonia.Base/Animation/SpringTypeConverter.cs
+++ b/src/Avalonia.Base/Animation/SpringTypeConverter.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Animation;
 /// <summary>
 /// Converts string values to <see cref="Spring"/> values.
 /// </summary>
-public class SpringTypeConverter : TypeConverter
+internal class SpringTypeConverter : TypeConverter
 {
     public override bool CanConvertFrom(ITypeDescriptorContext? context, Type sourceType)
     {
diff --git a/src/Avalonia.Base/Animation/Transition.cs b/src/Avalonia.Base/Animation/Transition.cs
index d307f348c4..519ed52578 100644
--- a/src/Avalonia.Base/Animation/Transition.cs
+++ b/src/Avalonia.Base/Animation/Transition.cs
@@ -53,10 +53,13 @@ namespace Avalonia.Animation
         /// <summary>
         /// Apply interpolation to the property.
         /// </summary>
-        public abstract IObservable<T> DoTransition(IObservable<double> progress, T oldValue, T newValue);
+        internal abstract IObservable<T> DoTransition(IObservable<double> progress, T oldValue, T newValue);
 
         /// <inheritdocs/>
-        public virtual IDisposable Apply(Animatable control, IClock clock, object? oldValue, object? newValue)
+        IDisposable ITransition.Apply(Animatable control, IClock clock, object? oldValue, object? newValue)
+            => Apply(control, clock, oldValue, newValue);
+        
+        internal virtual IDisposable Apply(Animatable control, IClock clock, object? oldValue, object? newValue)
         {
             if (Property is null)
                 throw new InvalidOperationException("Transition has no property specified.");
diff --git a/src/Avalonia.Base/Animation/TransitionObservableBase.cs b/src/Avalonia.Base/Animation/TransitionObservableBase.cs
index c4ac803135..92462dc537 100644
--- a/src/Avalonia.Base/Animation/TransitionObservableBase.cs
+++ b/src/Avalonia.Base/Animation/TransitionObservableBase.cs
@@ -10,13 +10,13 @@ namespace Avalonia.Animation
     /// Provides base for observables implementing transitions.
     /// </summary>
     /// <typeparam name="T">Type of the transitioned value.</typeparam>
-    public abstract class TransitionObservableBase<T> : SingleSubscriberObservableBase<T>, IObserver<double>
+    internal abstract class TransitionObservableBase<T> : SingleSubscriberObservableBase<T>, IObserver<double>
     {
-        private readonly Easing _easing;
+        private readonly IEasing _easing;
         private readonly IObservable<double> _progress;
         private IDisposable? _progressSubscription;
 
-        protected TransitionObservableBase(IObservable<double> progress, Easing easing)
+        protected TransitionObservableBase(IObservable<double> progress, IEasing easing)
         {
             _progress = progress;
             _easing = easing;
diff --git a/src/Avalonia.Base/Animation/Transitions.cs b/src/Avalonia.Base/Animation/Transitions.cs
index 6687a2902d..d94ecdc886 100644
--- a/src/Avalonia.Base/Animation/Transitions.cs
+++ b/src/Avalonia.Base/Animation/Transitions.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Animation
     /// <summary>
     /// A collection of <see cref="ITransition"/> definitions.
     /// </summary>
-    public class Transitions : AvaloniaList<ITransition>
+    public sealed class Transitions : AvaloniaList<ITransition>
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="Transitions"/> class.
diff --git a/src/Avalonia.Base/Animation/Transitions/BoxShadowsTransition.cs b/src/Avalonia.Base/Animation/Transitions/BoxShadowsTransition.cs
index 8a070836e9..cb36539938 100644
--- a/src/Avalonia.Base/Animation/Transitions/BoxShadowsTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/BoxShadowsTransition.cs
@@ -1,3 +1,4 @@
+using System;
 using Avalonia.Animation.Animators;
 using Avalonia.Media;
 
@@ -6,7 +7,10 @@ namespace Avalonia.Animation
     /// <summary>
     /// Transition class that handles <see cref="AvaloniaProperty"/> with <see cref="BoxShadows"/> type.
     /// </summary>  
-    public class BoxShadowsTransition : AnimatorDrivenTransition<BoxShadows, BoxShadowsAnimator>
+    public class BoxShadowsTransition : Transition<BoxShadows>
     {
+        internal override IObservable<BoxShadows> DoTransition(IObservable<double> progress, BoxShadows oldValue,
+            BoxShadows newValue) =>
+            AnimatorDrivenTransition<BoxShadows, BoxShadowsAnimator>.Transition(Easing, progress, oldValue, newValue);
     }
 }
diff --git a/src/Avalonia.Base/Animation/Transitions/BrushTransition.cs b/src/Avalonia.Base/Animation/Transitions/BrushTransition.cs
index 4d9c8af4d5..7e2c56e7b6 100644
--- a/src/Avalonia.Base/Animation/Transitions/BrushTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/BrushTransition.cs
@@ -16,7 +16,7 @@ namespace Avalonia.Animation
         private static readonly GradientBrushAnimator s_gradientAnimator = new GradientBrushAnimator();
         private static readonly ISolidColorBrushAnimator s_solidColorBrushAnimator = new ISolidColorBrushAnimator();
 
-        public override IObservable<IBrush?> DoTransition(IObservable<double> progress, IBrush? oldValue, IBrush? newValue)
+        internal override IObservable<IBrush?> DoTransition(IObservable<double> progress, IBrush? oldValue, IBrush? newValue)
         {
             if (oldValue is null || newValue is null)
             {
diff --git a/src/Avalonia.Base/Animation/Transitions/ColorTransition.cs b/src/Avalonia.Base/Animation/Transitions/ColorTransition.cs
index 9b925a3779..620f8524b1 100644
--- a/src/Avalonia.Base/Animation/Transitions/ColorTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/ColorTransition.cs
@@ -1,4 +1,5 @@
-using Avalonia.Animation.Animators;
+using System;
+using Avalonia.Animation.Animators;
 using Avalonia.Media;
 
 namespace Avalonia.Animation
@@ -6,7 +7,9 @@ namespace Avalonia.Animation
     /// <summary>
     /// Transition class that handles <see cref="AvaloniaProperty"/> with <see cref="Color"/> type.
     /// </summary>
-    public class ColorTransition : AnimatorDrivenTransition<Color, ColorAnimator>
+    public class ColorTransition : Transition<Color>
     {
+        internal override IObservable<Color> DoTransition(IObservable<double> progress, Color oldValue, Color newValue)
+            => AnimatorDrivenTransition<Color, ColorAnimator>.Transition(Easing, progress, oldValue, newValue);
     }
 }
diff --git a/src/Avalonia.Base/Animation/Transitions/CornerRadiusTransition.cs b/src/Avalonia.Base/Animation/Transitions/CornerRadiusTransition.cs
index 62b77a64e1..30bf16a14d 100644
--- a/src/Avalonia.Base/Animation/Transitions/CornerRadiusTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/CornerRadiusTransition.cs
@@ -1,3 +1,4 @@
+using System;
 using Avalonia.Animation.Animators;
 
 namespace Avalonia.Animation
@@ -5,7 +6,11 @@ namespace Avalonia.Animation
     /// <summary>
     /// Transition class that handles <see cref="AvaloniaProperty"/> with <see cref="CornerRadius"/> type.
     /// </summary>  
-    public class CornerRadiusTransition : AnimatorDrivenTransition<CornerRadius, CornerRadiusAnimator>
+    public class CornerRadiusTransition : Transition<CornerRadius>
     {
+        internal override IObservable<CornerRadius> DoTransition(IObservable<double> progress, CornerRadius oldValue,
+            CornerRadius newValue) =>
+            AnimatorDrivenTransition<CornerRadius, CornerRadiusAnimator>.Transition(Easing, progress, oldValue,
+                newValue);
     }
 }
diff --git a/src/Avalonia.Base/Animation/Transitions/DoubleTransition.cs b/src/Avalonia.Base/Animation/Transitions/DoubleTransition.cs
index 7232d87863..fa17cd1eb3 100644
--- a/src/Avalonia.Base/Animation/Transitions/DoubleTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/DoubleTransition.cs
@@ -1,3 +1,4 @@
+using System;
 using Avalonia.Animation.Animators;
 
 namespace Avalonia.Animation
@@ -5,7 +6,9 @@ namespace Avalonia.Animation
     /// <summary>
     /// Transition class that handles <see cref="AvaloniaProperty"/> with <see cref="double"/> types.
     /// </summary>  
-    public class DoubleTransition : AnimatorDrivenTransition<double, DoubleAnimator>
+    public class DoubleTransition : Transition<double>
     {
+        internal override IObservable<double> DoTransition(IObservable<double> progress, double oldValue, double newValue) => 
+            AnimatorDrivenTransition<double, DoubleAnimator>.Transition(Easing, progress, oldValue, newValue);
     }
 }
diff --git a/src/Avalonia.Base/Animation/Transitions/FloatTransition.cs b/src/Avalonia.Base/Animation/Transitions/FloatTransition.cs
index a96db8ba5b..0b109d0851 100644
--- a/src/Avalonia.Base/Animation/Transitions/FloatTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/FloatTransition.cs
@@ -1,3 +1,4 @@
+using System;
 using Avalonia.Animation.Animators;
 
 namespace Avalonia.Animation
@@ -5,7 +6,9 @@ namespace Avalonia.Animation
     /// <summary>
     /// Transition class that handles <see cref="AvaloniaProperty"/> with <see cref="float"/> types.
     /// </summary>  
-    public class FloatTransition : AnimatorDrivenTransition<float, FloatAnimator>
+    public class FloatTransition : Transition<float>
     {
+        internal override IObservable<float> DoTransition(IObservable<double> progress, float oldValue, float newValue) => 
+            AnimatorDrivenTransition<float, FloatAnimator>.Transition(Easing, progress, oldValue, newValue);
     }
 }
diff --git a/src/Avalonia.Base/Animation/Transitions/IntegerTransition.cs b/src/Avalonia.Base/Animation/Transitions/IntegerTransition.cs
index 343da7b689..c5a866d9cb 100644
--- a/src/Avalonia.Base/Animation/Transitions/IntegerTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/IntegerTransition.cs
@@ -1,3 +1,4 @@
+using System;
 using Avalonia.Animation.Animators;
 
 namespace Avalonia.Animation
@@ -5,7 +6,9 @@ namespace Avalonia.Animation
     /// <summary>
     /// Transition class that handles <see cref="AvaloniaProperty"/> with <see cref="int"/> types.
     /// </summary>  
-    public class IntegerTransition : AnimatorDrivenTransition<int, Int32Animator>
+    public class IntegerTransition : Transition<int>
     {
+        internal override IObservable<int> DoTransition(IObservable<double> progress, int oldValue, int newValue) => 
+            AnimatorDrivenTransition<int, Int32Animator>.Transition(Easing, progress, oldValue, newValue);
     }
 }
diff --git a/src/Avalonia.Base/Animation/Transitions/PointTransition.cs b/src/Avalonia.Base/Animation/Transitions/PointTransition.cs
index 0985aaa8f8..e1c4cfccf5 100644
--- a/src/Avalonia.Base/Animation/Transitions/PointTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/PointTransition.cs
@@ -1,3 +1,4 @@
+using System;
 using Avalonia.Animation.Animators;
 
 namespace Avalonia.Animation
@@ -5,7 +6,9 @@ namespace Avalonia.Animation
     /// <summary>
     /// Transition class that handles <see cref="AvaloniaProperty"/> with <see cref="Point"/> type.
     /// </summary>  
-    public class PointTransition : AnimatorDrivenTransition<Point, PointAnimator>
+    public class PointTransition : Transition<Point>
     {
+        internal override IObservable<Point> DoTransition(IObservable<double> progress, Point oldValue, Point newValue) => 
+            AnimatorDrivenTransition<Point, PointAnimator>.Transition(Easing, progress, oldValue, newValue);
     }
 }
diff --git a/src/Avalonia.Base/Animation/Transitions/RelativePointTransition.cs b/src/Avalonia.Base/Animation/Transitions/RelativePointTransition.cs
index 4a7bfa8384..6828bffbe8 100644
--- a/src/Avalonia.Base/Animation/Transitions/RelativePointTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/RelativePointTransition.cs
@@ -1,3 +1,4 @@
+using System;
 using Avalonia.Animation.Animators;
 
 namespace Avalonia.Animation
@@ -5,7 +6,9 @@ namespace Avalonia.Animation
     /// <summary>
     /// Transition class that handles <see cref="AvaloniaProperty"/> with <see cref="RelativePoint"/> type.
     /// </summary>  
-    public class RelativePointTransition : AnimatorDrivenTransition<RelativePoint, RelativePointAnimator>
+    public class RelativePointTransition : Transition<RelativePoint>
     {
+        internal override IObservable<RelativePoint> DoTransition(IObservable<double> progress, RelativePoint oldValue, RelativePoint newValue) =>
+            AnimatorDrivenTransition<RelativePoint, RelativePointAnimator>.Transition(Easing, progress, oldValue, newValue);
     }
 }
diff --git a/src/Avalonia.Base/Animation/Transitions/SizeTransition.cs b/src/Avalonia.Base/Animation/Transitions/SizeTransition.cs
index 6e59fb3631..790d2b8e6c 100644
--- a/src/Avalonia.Base/Animation/Transitions/SizeTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/SizeTransition.cs
@@ -1,3 +1,4 @@
+using System;
 using Avalonia.Animation.Animators;
 
 namespace Avalonia.Animation
@@ -5,7 +6,9 @@ namespace Avalonia.Animation
     /// <summary>
     /// Transition class that handles <see cref="AvaloniaProperty"/> with <see cref="Size"/> type.
     /// </summary>  
-    public class SizeTransition : AnimatorDrivenTransition<Size, SizeAnimator>
+    public class SizeTransition : Transition<Size>
     {
+        internal override IObservable<Size> DoTransition(IObservable<double> progress, Size oldValue, Size newValue) => 
+            AnimatorDrivenTransition<Size, SizeAnimator>.Transition(Easing, progress, oldValue, newValue);
     }
 }
diff --git a/src/Avalonia.Base/Animation/Transitions/ThicknessTransition.cs b/src/Avalonia.Base/Animation/Transitions/ThicknessTransition.cs
index f50929348f..fd188dab43 100644
--- a/src/Avalonia.Base/Animation/Transitions/ThicknessTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/ThicknessTransition.cs
@@ -1,3 +1,4 @@
+using System;
 using Avalonia.Animation.Animators;
 
 namespace Avalonia.Animation
@@ -5,7 +6,9 @@ namespace Avalonia.Animation
     /// <summary>
     /// Transition class that handles <see cref="AvaloniaProperty"/> with <see cref="Thickness"/> type.
     /// </summary>  
-    public class ThicknessTransition : AnimatorDrivenTransition<Thickness, ThicknessAnimator>
+    public class ThicknessTransition : Transition<Thickness>
     {
+        internal override IObservable<Thickness> DoTransition(IObservable<double> progress, Thickness oldValue, Thickness newValue) => 
+            AnimatorDrivenTransition<Thickness, ThicknessAnimator>.Transition(Easing, progress, oldValue, newValue);
     }
 }
diff --git a/src/Avalonia.Base/Animation/Transitions/TransformOperationsTransition.cs b/src/Avalonia.Base/Animation/Transitions/TransformOperationsTransition.cs
index 73fc23ad99..ad73a05cb6 100644
--- a/src/Avalonia.Base/Animation/Transitions/TransformOperationsTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/TransformOperationsTransition.cs
@@ -11,7 +11,7 @@ namespace Avalonia.Animation
     {
         private static readonly TransformOperationsAnimator s_operationsAnimator = new TransformOperationsAnimator();
 
-        public override IObservable<ITransform> DoTransition(
+        internal override IObservable<ITransform> DoTransition(
             IObservable<double> progress,
             ITransform oldValue,
             ITransform newValue)
diff --git a/src/Avalonia.Base/Animation/Transitions/VectorTransition.cs b/src/Avalonia.Base/Animation/Transitions/VectorTransition.cs
index 596989fbae..b293d1f7cf 100644
--- a/src/Avalonia.Base/Animation/Transitions/VectorTransition.cs
+++ b/src/Avalonia.Base/Animation/Transitions/VectorTransition.cs
@@ -1,3 +1,4 @@
+using System;
 using Avalonia.Animation.Animators;
 
 namespace Avalonia.Animation
@@ -5,7 +6,9 @@ namespace Avalonia.Animation
     /// <summary>
     /// Transition class that handles <see cref="AvaloniaProperty"/> with <see cref="Vector"/> type.
     /// </summary>  
-    public class VectorTransition : AnimatorDrivenTransition<Vector, VectorAnimator>
+    public class VectorTransition : Transition<Vector>
     {
+        internal override IObservable<Vector> DoTransition(IObservable<double> progress, Vector oldValue, Vector newValue) => 
+            AnimatorDrivenTransition<Vector, VectorAnimator>.Transition(Easing, progress, oldValue, newValue);
     }
 }
diff --git a/src/Avalonia.Base/AvaloniaLocator.cs b/src/Avalonia.Base/AvaloniaLocator.cs
index 8ec245507b..1fd266cca3 100644
--- a/src/Avalonia.Base/AvaloniaLocator.cs
+++ b/src/Avalonia.Base/AvaloniaLocator.cs
@@ -1,10 +1,12 @@
 using System;
 using System.Collections.Generic;
+using Avalonia.Metadata;
 
 #pragma warning disable CS1591 // Enable me later
 
 namespace Avalonia
 {
+    [PrivateApi]
     public class AvaloniaLocator : IAvaloniaDependencyResolver
     {
         private readonly IAvaloniaDependencyResolver? _parentScope;
@@ -114,11 +116,13 @@ namespace Avalonia
         }
     }
 
+    [PrivateApi]
     public interface IAvaloniaDependencyResolver
     {
         object? GetService(Type t);
     }
 
+    [PrivateApi]
     public static class LocatorExtensions
     {
         public static T? GetService<T>(this IAvaloniaDependencyResolver resolver)
diff --git a/src/Avalonia.Base/Data/TemplateBinding.cs b/src/Avalonia.Base/Data/TemplateBinding.cs
index 09f04dfe70..0fd40cd09d 100644
--- a/src/Avalonia.Base/Data/TemplateBinding.cs
+++ b/src/Avalonia.Base/Data/TemplateBinding.cs
@@ -3,18 +3,21 @@ using System.Globalization;
 using Avalonia.Data.Converters;
 using Avalonia.Reactive;
 using Avalonia.Styling;
+using Avalonia.Threading;
 
 namespace Avalonia.Data
 {
     /// <summary>
     /// A XAML binding to a property on a control's templated parent.
     /// </summary>
-    public class TemplateBinding : SingleSubscriberObservableBase<object?>,
+    public class TemplateBinding : IObservable<object?>,
         IBinding,
         IDescription,
         IAvaloniaSubject<object?>,
-        ISetterValue
+        ISetterValue,
+        IDisposable
     {
+        private IObserver<object?>? _observer;
         private bool _isSetterValue;
         private StyledElement? _target;
         private Type? _targetType;
@@ -29,6 +32,28 @@ namespace Avalonia.Data
             Property = property;
         }
 
+        public IDisposable Subscribe(IObserver<object?> observer)
+        {
+            _ = observer ?? throw new ArgumentNullException(nameof(observer));
+            Dispatcher.UIThread.VerifyAccess();
+
+            if (_observer != null)
+            {
+                throw new InvalidOperationException("The observable can only be subscribed once.");
+            }
+
+            _observer = observer;
+            Subscribed();
+
+            return this;
+        }
+
+        public virtual void Dispose()
+        {
+            Unsubscribed();
+            _observer = null;
+        }
+
         /// <inheritdoc/>
         public InstancedBinding? Initiate(
             AvaloniaObject target,
@@ -111,7 +136,7 @@ namespace Avalonia.Data
         /// <inheritdoc/>
         void ISetterValue.Initialize(SetterBase setter) => _isSetterValue = true;
 
-        protected override void Subscribed()
+        private void Subscribed()
         {
             TemplatedParentChanged();
 
@@ -121,7 +146,7 @@ namespace Avalonia.Data
             }
         }
 
-        protected override void Unsubscribed()
+        private void Unsubscribed()
         {
             if (_target?.TemplatedParent is { } templatedParent)
             {
@@ -147,12 +172,12 @@ namespace Avalonia.Data
                     value = Converter.Convert(value, _targetType ?? typeof(object), ConverterParameter, CultureInfo.CurrentCulture);
                 }
 
-                PublishNext(value);
+                _observer?.OnNext(value);
                 _hasProducedValue = true;
             }
             else if (_hasProducedValue)
             {
-                PublishNext(AvaloniaProperty.UnsetValue);
+                _observer?.OnNext(AvaloniaProperty.UnsetValue);
                 _hasProducedValue = false;
             }
         }
diff --git a/src/Avalonia.Base/Input/AccessKeyHandler.cs b/src/Avalonia.Base/Input/AccessKeyHandler.cs
index 2b8786089f..2e0268a644 100644
--- a/src/Avalonia.Base/Input/AccessKeyHandler.cs
+++ b/src/Avalonia.Base/Input/AccessKeyHandler.cs
@@ -65,14 +65,14 @@ namespace Avalonia.Input
             {
                 if (_mainMenu != null)
                 {
-                    _mainMenu.MenuClosed -= MainMenuClosed;
+                    _mainMenu.Closed -= MainMenuClosed;
                 }
 
                 _mainMenu = value;
 
                 if (_mainMenu != null)
                 {
-                    _mainMenu.MenuClosed += MainMenuClosed;
+                    _mainMenu.Closed += MainMenuClosed;
                 }
             }
         }
diff --git a/src/Avalonia.Base/Input/DragDropDevice.cs b/src/Avalonia.Base/Input/DragDropDevice.cs
index 04d4693352..5ad20111fc 100644
--- a/src/Avalonia.Base/Input/DragDropDevice.cs
+++ b/src/Avalonia.Base/Input/DragDropDevice.cs
@@ -2,9 +2,11 @@
 using Avalonia.VisualTree;
 using System.Linq;
 using Avalonia.Input.Raw;
+using Avalonia.Metadata;
 
 namespace Avalonia.Input
 {
+    [PrivateApi]
     public class DragDropDevice : IDragDropDevice
     {
         public static readonly DragDropDevice Instance = new DragDropDevice();
diff --git a/src/Avalonia.Base/Input/IInputDevice.cs b/src/Avalonia.Base/Input/IInputDevice.cs
index fe4f584f18..658b87c6b2 100644
--- a/src/Avalonia.Base/Input/IInputDevice.cs
+++ b/src/Avalonia.Base/Input/IInputDevice.cs
@@ -3,7 +3,7 @@ using Avalonia.Metadata;
 
 namespace Avalonia.Input
 {
-    [NotClientImplementable]
+    [NotClientImplementable, PrivateApi]
     public interface IInputDevice
     {
         /// <summary>
diff --git a/src/Avalonia.Base/Input/IInputManager.cs b/src/Avalonia.Base/Input/IInputManager.cs
index 658226a519..fc18799e7a 100644
--- a/src/Avalonia.Base/Input/IInputManager.cs
+++ b/src/Avalonia.Base/Input/IInputManager.cs
@@ -8,7 +8,7 @@ namespace Avalonia.Input
     /// Receives input from the windowing subsystem and dispatches it to interested parties
     /// for processing.
     /// </summary>
-    [NotClientImplementable]
+    [NotClientImplementable, PrivateApi]
     public interface IInputManager
     {
         /// <summary>
diff --git a/src/Avalonia.Base/Input/IKeyboardNavigationHandler.cs b/src/Avalonia.Base/Input/IKeyboardNavigationHandler.cs
index 3bcd6d6206..6ab0031f31 100644
--- a/src/Avalonia.Base/Input/IKeyboardNavigationHandler.cs
+++ b/src/Avalonia.Base/Input/IKeyboardNavigationHandler.cs
@@ -15,6 +15,7 @@ namespace Avalonia.Input
         /// <remarks>
         /// This method can only be called once, typically by the owner itself on creation.
         /// </remarks>
+        [PrivateApi]
         void SetOwner(IInputRoot owner);
 
         /// <summary>
diff --git a/src/Avalonia.Base/Input/IMainMenu.cs b/src/Avalonia.Base/Input/IMainMenu.cs
index cc1b88d4c3..02437b6367 100644
--- a/src/Avalonia.Base/Input/IMainMenu.cs
+++ b/src/Avalonia.Base/Input/IMainMenu.cs
@@ -26,6 +26,6 @@ namespace Avalonia.Input
         /// <summary>
         /// Occurs when the main menu closes.
         /// </summary>
-        event EventHandler<RoutedEventArgs>? MenuClosed;
+        event EventHandler<RoutedEventArgs>? Closed;
     }
 }
diff --git a/src/Avalonia.Base/Input/InputManager.cs b/src/Avalonia.Base/Input/InputManager.cs
index e87665fd54..c9b1751b2a 100644
--- a/src/Avalonia.Base/Input/InputManager.cs
+++ b/src/Avalonia.Base/Input/InputManager.cs
@@ -8,7 +8,7 @@ namespace Avalonia.Input
     /// Receives input from the windowing subsystem and dispatches it to interested parties
     /// for processing.
     /// </summary>
-    public class InputManager : IInputManager
+    internal class InputManager : IInputManager
     {
         private readonly LightweightSubject<RawInputEventArgs> _preProcess = new();
         private readonly LightweightSubject<RawInputEventArgs> _process = new();
diff --git a/src/Avalonia.Base/Input/KeyboardNavigationHandler.cs b/src/Avalonia.Base/Input/KeyboardNavigationHandler.cs
index 7a83501ce4..d979acbdf4 100644
--- a/src/Avalonia.Base/Input/KeyboardNavigationHandler.cs
+++ b/src/Avalonia.Base/Input/KeyboardNavigationHandler.cs
@@ -10,7 +10,7 @@ namespace Avalonia.Input
     /// Handles keyboard navigation for a window.
     /// </summary>
     [Unstable]
-    public class KeyboardNavigationHandler : IKeyboardNavigationHandler
+    public sealed class KeyboardNavigationHandler : IKeyboardNavigationHandler
     {
         /// <summary>
         /// The window to which the handler belongs.
@@ -24,6 +24,7 @@ namespace Avalonia.Input
         /// <remarks>
         /// This method can only be called once, typically by the owner itself on creation.
         /// </remarks>
+        [PrivateApi]
         public void SetOwner(IInputRoot owner)
         {
             if (_owner != null)
@@ -102,7 +103,7 @@ namespace Avalonia.Input
         /// </summary>
         /// <param name="sender">The event sender.</param>
         /// <param name="e">The event args.</param>
-        protected virtual void OnKeyDown(object? sender, KeyEventArgs e)
+        void OnKeyDown(object? sender, KeyEventArgs e)
         {
             if (e.Key == Key.Tab)
             {
diff --git a/src/Avalonia.Base/Input/PointerEventArgs.cs b/src/Avalonia.Base/Input/PointerEventArgs.cs
index 7f82199b56..9c24e5c314 100644
--- a/src/Avalonia.Base/Input/PointerEventArgs.cs
+++ b/src/Avalonia.Base/Input/PointerEventArgs.cs
@@ -70,6 +70,17 @@ namespace Avalonia.Input
             if (relativeTo == null)
                 return pt;
 
+            // If the visual the user passed in, is not connected to the same visual root
+            // (i.e. they called it for a control inside a popup.
+            if (!ReferenceEquals(_rootVisual, relativeTo.VisualRoot) && relativeTo.VisualRoot is { })
+            {
+                // Convert to absolute screen coordinates.
+                var screenPt = _rootVisual.PointToScreen(pt);
+
+                // Convert to client co-ordinates of the visual inside the other visual root.
+                return relativeTo.PointToClient(screenPt);
+            }
+
             return pt * _rootVisual.TransformToVisual(relativeTo) ?? default;
         }
 
diff --git a/src/Avalonia.Base/Input/Raw/RawDragEvent.cs b/src/Avalonia.Base/Input/Raw/RawDragEvent.cs
index c903aad684..8ade3d8af5 100644
--- a/src/Avalonia.Base/Input/Raw/RawDragEvent.cs
+++ b/src/Avalonia.Base/Input/Raw/RawDragEvent.cs
@@ -1,7 +1,9 @@
 using System;
+using Avalonia.Metadata;
 
 namespace Avalonia.Input.Raw
 {
+    [PrivateApi]
     public class RawDragEvent : RawInputEventArgs
     {
         public Point Location { get; set; }
diff --git a/src/Avalonia.Base/Input/Raw/RawInputEventArgs.cs b/src/Avalonia.Base/Input/Raw/RawInputEventArgs.cs
index cf4d37b6da..fa1953de50 100644
--- a/src/Avalonia.Base/Input/Raw/RawInputEventArgs.cs
+++ b/src/Avalonia.Base/Input/Raw/RawInputEventArgs.cs
@@ -1,4 +1,5 @@
 using System;
+using Avalonia.Metadata;
 
 namespace Avalonia.Input.Raw
 {
@@ -11,6 +12,7 @@ namespace Avalonia.Input.Raw
     /// pre-processing they are consumed by the relevant <see cref="Device"/> and turned into
     /// standard Avalonia events.
     /// </remarks>
+    [PrivateApi]
     public class RawInputEventArgs : EventArgs
     {
         /// <summary>
diff --git a/src/Avalonia.Base/Input/Raw/RawKeyEventArgs.cs b/src/Avalonia.Base/Input/Raw/RawKeyEventArgs.cs
index 6ed073d006..b80d09e420 100644
--- a/src/Avalonia.Base/Input/Raw/RawKeyEventArgs.cs
+++ b/src/Avalonia.Base/Input/Raw/RawKeyEventArgs.cs
@@ -1,3 +1,5 @@
+using Avalonia.Metadata;
+
 namespace Avalonia.Input.Raw
 {
     public enum RawKeyEventType
@@ -6,6 +8,7 @@ namespace Avalonia.Input.Raw
         KeyUp
     }
 
+    [PrivateApi]
     public class RawKeyEventArgs : RawInputEventArgs
     {
         public RawKeyEventArgs(
diff --git a/src/Avalonia.Base/Input/Raw/RawMouseWheelEventArgs.cs b/src/Avalonia.Base/Input/Raw/RawMouseWheelEventArgs.cs
index a752275980..e370ca3708 100644
--- a/src/Avalonia.Base/Input/Raw/RawMouseWheelEventArgs.cs
+++ b/src/Avalonia.Base/Input/Raw/RawMouseWheelEventArgs.cs
@@ -1,6 +1,9 @@
 
+using Avalonia.Metadata;
+
 namespace Avalonia.Input.Raw
 {
+    [PrivateApi]
     public class RawMouseWheelEventArgs : RawPointerEventArgs
     {
         public RawMouseWheelEventArgs(
diff --git a/src/Avalonia.Base/Input/Raw/RawPointerEventArgs.cs b/src/Avalonia.Base/Input/Raw/RawPointerEventArgs.cs
index ebedc9e6e8..595f4c0c66 100644
--- a/src/Avalonia.Base/Input/Raw/RawPointerEventArgs.cs
+++ b/src/Avalonia.Base/Input/Raw/RawPointerEventArgs.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using Avalonia.Metadata;
 
 namespace Avalonia.Input.Raw
 {
@@ -31,6 +32,7 @@ namespace Avalonia.Input.Raw
     /// <summary>
     /// A raw mouse event.
     /// </summary>
+    [PrivateApi]
     public class RawPointerEventArgs : RawInputEventArgs
     {
         private RawPointerPoint _point;
@@ -124,6 +126,7 @@ namespace Avalonia.Input.Raw
         internal IInputElement? InputHitTestResult { get; set; }
     }
 
+    [PrivateApi]
     public record struct RawPointerPoint
     {
         /// <summary>
diff --git a/src/Avalonia.Base/Input/Raw/RawPointerGestureEventArgs.cs b/src/Avalonia.Base/Input/Raw/RawPointerGestureEventArgs.cs
index 5a6dbda9a7..379ca65ea8 100644
--- a/src/Avalonia.Base/Input/Raw/RawPointerGestureEventArgs.cs
+++ b/src/Avalonia.Base/Input/Raw/RawPointerGestureEventArgs.cs
@@ -1,5 +1,8 @@
+using Avalonia.Metadata;
+
 namespace Avalonia.Input.Raw
 {
+    [PrivateApi]
     public class RawPointerGestureEventArgs : RawPointerEventArgs
     {
         public RawPointerGestureEventArgs(
diff --git a/src/Avalonia.Base/Input/Raw/RawSizeEventArgs.cs b/src/Avalonia.Base/Input/Raw/RawSizeEventArgs.cs
index b6a364eab9..a0eb5934eb 100644
--- a/src/Avalonia.Base/Input/Raw/RawSizeEventArgs.cs
+++ b/src/Avalonia.Base/Input/Raw/RawSizeEventArgs.cs
@@ -1,7 +1,9 @@
 using System;
+using Avalonia.Metadata;
 
 namespace Avalonia.Input.Raw
 {
+    [PrivateApi]
     public class RawSizeEventArgs : EventArgs
     {
         public RawSizeEventArgs(Size size)
diff --git a/src/Avalonia.Base/Input/Raw/RawTextInputEventArgs.cs b/src/Avalonia.Base/Input/Raw/RawTextInputEventArgs.cs
index cd1cf29bcf..3ecbf24bdd 100644
--- a/src/Avalonia.Base/Input/Raw/RawTextInputEventArgs.cs
+++ b/src/Avalonia.Base/Input/Raw/RawTextInputEventArgs.cs
@@ -1,5 +1,8 @@
+using Avalonia.Metadata;
+
 namespace Avalonia.Input.Raw
 {
+    [PrivateApi]
     public class RawTextInputEventArgs : RawInputEventArgs
     {
         public RawTextInputEventArgs(
diff --git a/src/Avalonia.Base/Input/Raw/RawTouchEventArgs.cs b/src/Avalonia.Base/Input/Raw/RawTouchEventArgs.cs
index 3e842e6e3f..7adab89d2e 100644
--- a/src/Avalonia.Base/Input/Raw/RawTouchEventArgs.cs
+++ b/src/Avalonia.Base/Input/Raw/RawTouchEventArgs.cs
@@ -1,7 +1,9 @@
 using System;
+using Avalonia.Metadata;
 
 namespace Avalonia.Input.Raw
 {
+    [PrivateApi]
     public class RawTouchEventArgs : RawPointerEventArgs
     {
         public RawTouchEventArgs(IInputDevice device, ulong timestamp, IInputRoot root,
diff --git a/src/Avalonia.Base/Input/TextInput/TransformTrackingHelper.cs b/src/Avalonia.Base/Input/TextInput/TransformTrackingHelper.cs
index 36ee1fff27..1ea754f0f4 100644
--- a/src/Avalonia.Base/Input/TextInput/TransformTrackingHelper.cs
+++ b/src/Avalonia.Base/Input/TextInput/TransformTrackingHelper.cs
@@ -91,7 +91,7 @@ namespace Avalonia.Input.TextInput
             if(_queuedForUpdate)
                 return;
             _queuedForUpdate = true;
-            Dispatcher.UIThread.Post(UpdateMatrix, DispatcherPriority.Render);
+            Dispatcher.UIThread.Post(UpdateMatrix, DispatcherPriority.AfterRender);
         }
 
         private void PropertyChangedHandler(object? sender, AvaloniaPropertyChangedEventArgs e)
diff --git a/src/Avalonia.Base/Interactivity/RoutedPropertyChangedEventArgs.cs b/src/Avalonia.Base/Interactivity/RoutedPropertyChangedEventArgs.cs
deleted file mode 100644
index 22134b518d..0000000000
--- a/src/Avalonia.Base/Interactivity/RoutedPropertyChangedEventArgs.cs
+++ /dev/null
@@ -1,46 +0,0 @@
-namespace Avalonia.Interactivity
-{
-    /// <summary>
-    /// Provides both old and new property values with a routed event.
-    /// </summary>
-    /// <typeparam name="T">The type of values.</typeparam>
-    public class RoutedPropertyChangedEventArgs<T> : RoutedEventArgs
-    {
-        /// <summary>
-        /// Initializes a new instance of the <see cref="RoutedPropertyChangedEventArgs{T}"/> class.
-        /// </summary>
-        /// <param name="oldValue">The old property value.</param>
-        /// <param name="newValue">The new property value.</param>
-        /// <param name="routedEvent">The routed event associated with these event args.</param>
-        public RoutedPropertyChangedEventArgs(T oldValue, T newValue, RoutedEvent? routedEvent)
-            : base(routedEvent)
-        {
-            OldValue = oldValue;
-            NewValue = newValue;
-        }
-
-        /// <summary>
-        /// Initializes a new instance of the <see cref="RoutedPropertyChangedEventArgs{T}"/> class.
-        /// </summary>
-        /// <param name="oldValue">The old property value.</param>
-        /// <param name="newValue">The new property value.</param>
-        /// <param name="routedEvent">The routed event associated with these event args.</param>
-        /// <param name="source">The source object that raised the routed event.</param>
-        public RoutedPropertyChangedEventArgs(T oldValue, T newValue, RoutedEvent? routedEvent, object? source)
-            : base(routedEvent, source)
-        {
-            OldValue = oldValue;
-            NewValue = newValue;
-        }
-
-        /// <summary>
-        /// Gets the old value of the property.
-        /// </summary>
-        public T OldValue { get; init; }
-
-        /// <summary>
-        /// Gets the new value of the property.
-        /// </summary>
-        public T NewValue { get; init; }
-    }
-}
diff --git a/src/Avalonia.Base/Layout/ILayoutManager.cs b/src/Avalonia.Base/Layout/ILayoutManager.cs
index 38d46557e1..063c8e99d2 100644
--- a/src/Avalonia.Base/Layout/ILayoutManager.cs
+++ b/src/Avalonia.Base/Layout/ILayoutManager.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Layout
     /// Manages measuring and arranging of controls.
     /// </summary>
     [NotClientImplementable]
-    public interface ILayoutManager : IDisposable
+    internal interface ILayoutManager : IDisposable
     {
         /// <summary>
         /// Raised when the layout manager completes a layout pass.
diff --git a/src/Avalonia.Base/Layout/ILayoutRoot.cs b/src/Avalonia.Base/Layout/ILayoutRoot.cs
index c90ddb9219..efea5bfed8 100644
--- a/src/Avalonia.Base/Layout/ILayoutRoot.cs
+++ b/src/Avalonia.Base/Layout/ILayoutRoot.cs
@@ -21,6 +21,6 @@ namespace Avalonia.Layout
         /// <summary>
         /// Associated instance of layout manager
         /// </summary>
-        ILayoutManager LayoutManager { get; }
+        internal ILayoutManager LayoutManager { get; }
     }
 }
diff --git a/src/Avalonia.Base/Layout/LayoutManager.cs b/src/Avalonia.Base/Layout/LayoutManager.cs
index 7873f83edb..6d698ae5ce 100644
--- a/src/Avalonia.Base/Layout/LayoutManager.cs
+++ b/src/Avalonia.Base/Layout/LayoutManager.cs
@@ -4,6 +4,7 @@ using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
 using Avalonia.Logging;
+using Avalonia.Media;
 using Avalonia.Rendering;
 using Avalonia.Threading;
 using Avalonia.Utilities;
@@ -15,24 +16,24 @@ namespace Avalonia.Layout
     /// <summary>
     /// Manages measuring and arranging of controls.
     /// </summary>
-    public class LayoutManager : ILayoutManager, IDisposable
+    internal class LayoutManager : ILayoutManager, IDisposable
     {
         private const int MaxPasses = 10;
         private readonly Layoutable _owner;
         private readonly LayoutQueue<Layoutable> _toMeasure = new LayoutQueue<Layoutable>(v => !v.IsMeasureValid);
         private readonly LayoutQueue<Layoutable> _toArrange = new LayoutQueue<Layoutable>(v => !v.IsArrangeValid);
         private readonly List<Layoutable> _toArrangeAfterMeasure = new();
-        private readonly Action _executeLayoutPass;
         private List<EffectiveViewportChangedListener>? _effectiveViewportChangedListeners;
         private bool _disposed;
         private bool _queued;
         private bool _running;
         private int _totalPassCount;
+        private Action _invokeOnRender;
 
         public LayoutManager(ILayoutRoot owner)
         {
             _owner = owner as Layoutable ?? throw new ArgumentNullException(nameof(owner));
-            _executeLayoutPass = ExecuteQueuedLayoutPass;
+            _invokeOnRender = ExecuteQueuedLayoutPass;
         }
 
         public virtual event EventHandler? LayoutUpdated;
@@ -99,7 +100,7 @@ namespace Avalonia.Layout
             QueueLayoutPass();
         }
 
-        private void ExecuteQueuedLayoutPass()
+        internal void ExecuteQueuedLayoutPass()
         {
             if (!_queued)
             {
@@ -346,7 +347,7 @@ namespace Avalonia.Layout
             if (!_queued && !_running)
             {
                 _queued = true;
-                Dispatcher.UIThread.Post(_executeLayoutPass, DispatcherPriority.Layout);
+                MediaContext.Instance.BeginInvokeOnRender(_invokeOnRender);
             }
         }
 
diff --git a/src/Avalonia.Base/Layout/Layoutable.cs b/src/Avalonia.Base/Layout/Layoutable.cs
index 08f327d048..f64c26ddf8 100644
--- a/src/Avalonia.Base/Layout/Layoutable.cs
+++ b/src/Avalonia.Base/Layout/Layoutable.cs
@@ -205,6 +205,15 @@ namespace Avalonia.Layout
             }
         }
 
+        /// <summary>
+        /// Executes a layout pass.
+        /// </summary>
+        /// <remarks>
+        /// You should not usually need to call this method explictly, the layout manager will
+        /// schedule layout passes itself.
+        /// </remarks>
+        public void UpdateLayout() => (this.GetVisualRoot() as ILayoutRoot)?.LayoutManager?.ExecuteLayoutPass();
+
         /// <summary>
         /// Gets or sets the width of the element.
         /// </summary>
diff --git a/src/Avalonia.Base/Media/Brush.cs b/src/Avalonia.Base/Media/Brush.cs
index 3c888d13cf..986e3221e6 100644
--- a/src/Avalonia.Base/Media/Brush.cs
+++ b/src/Avalonia.Base/Media/Brush.cs
@@ -118,7 +118,7 @@ namespace Avalonia.Media
                 OnReferencedFromCompositor(c);
         }
 
-        protected virtual void OnReferencedFromCompositor(Compositor c)
+        private protected virtual void OnReferencedFromCompositor(Compositor c)
         {
             if (Transform is ICompositionRenderResource<ITransform> resource)
                 resource.AddRefOnCompositor(c);
diff --git a/src/Avalonia.Base/Media/CharacterHit.cs b/src/Avalonia.Base/Media/CharacterHit.cs
index 6bbbff4f5b..27cf3a42dc 100644
--- a/src/Avalonia.Base/Media/CharacterHit.cs
+++ b/src/Avalonia.Base/Media/CharacterHit.cs
@@ -19,6 +19,7 @@ namespace Avalonia.Media
         /// <param name="firstCharacterIndex">Index of the first character that got hit.</param>
         /// <param name="trailingLength">In the case of a leading edge, this value is 0. In the case of a trailing edge,
         /// this value is the number of code points until the next valid caret position.</param>
+        [DebuggerStepThrough]
         public CharacterHit(int firstCharacterIndex, int trailingLength = 0)
         {
             FirstCharacterIndex = firstCharacterIndex;
diff --git a/src/Avalonia.Base/Media/DashStyle.cs b/src/Avalonia.Base/Media/DashStyle.cs
index 0efb764029..6e2cea417d 100644
--- a/src/Avalonia.Base/Media/DashStyle.cs
+++ b/src/Avalonia.Base/Media/DashStyle.cs
@@ -13,7 +13,7 @@ namespace Avalonia.Media
     /// <summary>
     /// Represents the sequence of dashes and gaps that will be applied by a <see cref="Pen"/>.
     /// </summary>
-    public class DashStyle : Animatable, IDashStyle
+    public sealed class DashStyle : Animatable, IDashStyle
     {
         /// <summary>
         /// Defines the <see cref="Dashes"/> property.
diff --git a/src/Avalonia.Base/Media/Drawing.cs b/src/Avalonia.Base/Media/Drawing.cs
index 867708f78d..584e5978fc 100644
--- a/src/Avalonia.Base/Media/Drawing.cs
+++ b/src/Avalonia.Base/Media/Drawing.cs
@@ -5,6 +5,11 @@
     /// </summary>
     public abstract class Drawing : AvaloniaObject
     {
+        internal Drawing()
+        {
+            
+        }
+        
         /// <summary>
         /// Draws this drawing to the given <see cref="DrawingContext"/>.
         /// </summary>
diff --git a/src/Avalonia.Base/Media/DrawingBrush.cs b/src/Avalonia.Base/Media/DrawingBrush.cs
index 89e9b9e075..b710351b98 100644
--- a/src/Avalonia.Base/Media/DrawingBrush.cs
+++ b/src/Avalonia.Base/Media/DrawingBrush.cs
@@ -12,7 +12,7 @@ namespace Avalonia.Media
     /// <summary>
     /// Paints an area with an <see cref="Drawing"/>.
     /// </summary>
-    public class DrawingBrush : TileBrush, ISceneBrush
+    public sealed class DrawingBrush : TileBrush, ISceneBrush
     {
         /// <summary>
         /// Defines the <see cref="Drawing"/> property.
@@ -60,7 +60,7 @@ namespace Avalonia.Media
 
         private InlineDictionary<Compositor, CompositionRenderDataSceneBrushContent?> _renderDataDictionary;
 
-        protected override void OnReferencedFromCompositor(Compositor c)
+        private protected override void OnReferencedFromCompositor(Compositor c)
         {
             _renderDataDictionary.Add(c, CreateServerContent(c));
             base.OnReferencedFromCompositor(c);
diff --git a/src/Avalonia.Base/Media/DrawingContext.cs b/src/Avalonia.Base/Media/DrawingContext.cs
index 02294368c5..c55d6de10f 100644
--- a/src/Avalonia.Base/Media/DrawingContext.cs
+++ b/src/Avalonia.Base/Media/DrawingContext.cs
@@ -360,16 +360,15 @@ namespace Avalonia.Media
         /// Pushes an opacity value.
         /// </summary>
         /// <param name="opacity">The opacity.</param>
-        /// <param name="bounds">The bounds.</param>
         /// <returns>A disposable used to undo the opacity.</returns>
-        public PushedState PushOpacity(double opacity, Rect bounds)
+        public PushedState PushOpacity(double opacity)
         {
-            PushOpacityCore(opacity, bounds);
+            PushOpacityCore(opacity);
             _states ??= StateStackPool.Get();
             _states.Push(new RestoreState(this, RestoreState.PushedStateType.Opacity));
             return new PushedState(this);
         }
-        protected abstract void PushOpacityCore(double opacity, Rect bounds);
+        protected abstract void PushOpacityCore(double opacity);
 
         /// <summary>
         /// Pushes an opacity mask.
diff --git a/src/Avalonia.Base/Media/DrawingGroup.cs b/src/Avalonia.Base/Media/DrawingGroup.cs
index dfcb5c1eb4..1f3c74c51c 100644
--- a/src/Avalonia.Base/Media/DrawingGroup.cs
+++ b/src/Avalonia.Base/Media/DrawingGroup.cs
@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using Avalonia.Media.Imaging;
 using Avalonia.Metadata;
 using Avalonia.Platform;
 using Avalonia.Rendering.SceneGraph;
@@ -8,7 +7,7 @@ using Avalonia.Utilities;
 
 namespace Avalonia.Media
 {
-    public class DrawingGroup : Drawing
+    public sealed class DrawingGroup : Drawing
     {
         public static readonly StyledProperty<double> OpacityProperty =
             AvaloniaProperty.Register<DrawingGroup, double>(nameof(Opacity), 1);
@@ -72,9 +71,8 @@ namespace Avalonia.Media
         internal override void DrawCore(DrawingContext context)
         {
             var bounds = GetBounds();
-
             using (context.PushTransform(Transform?.Value ?? Matrix.Identity))
-            using (context.PushOpacity(Opacity, bounds))
+            using (context.PushOpacity(Opacity))
             using (ClipGeometry != null ? context.PushGeometryClip(ClipGeometry) : default)
             using (OpacityMask != null ? context.PushOpacityMask(OpacityMask, bounds) : default)
             {
@@ -178,22 +176,30 @@ namespace Avalonia.Media
 
             protected override void PushClipCore(Rect rect)
             {
-                throw new NotImplementedException();
+                var drawingGroup = PushNewDrawingGroup();
+
+                drawingGroup.ClipGeometry = new RectangleGeometry(rect);
             }
 
             protected override void PushGeometryClipCore(Geometry clip)
             {
-                throw new NotImplementedException();
+                var drawingGroup = PushNewDrawingGroup();
+
+                drawingGroup.ClipGeometry = clip;
             }
 
-            protected override void PushOpacityCore(double opacity, Rect bounds)
+            protected override void PushOpacityCore(double opacity)
             {
-                throw new NotImplementedException();
+                var drawingGroup = PushNewDrawingGroup();
+
+                drawingGroup.Opacity = opacity;
             }
 
             protected override void PushOpacityMaskCore(IBrush mask, Rect bounds)
             {
-                throw new NotImplementedException();
+                var drawingGroup = PushNewDrawingGroup();
+
+                drawingGroup.OpacityMask = mask;
             }
 
             internal override void DrawBitmap(IRef<IBitmapImpl> source, double opacity, Rect sourceRect, Rect destRect)
diff --git a/src/Avalonia.Base/Media/Effects/BlurEffect.cs b/src/Avalonia.Base/Media/Effects/BlurEffect.cs
index 47c86e4e42..69682b65bc 100644
--- a/src/Avalonia.Base/Media/Effects/BlurEffect.cs
+++ b/src/Avalonia.Base/Media/Effects/BlurEffect.cs
@@ -2,7 +2,7 @@ using System;
 // ReSharper disable CheckNamespace
 namespace Avalonia.Media;
 
-public class BlurEffect : Effect, IBlurEffect, IMutableEffect
+public sealed class BlurEffect : Effect, IBlurEffect, IMutableEffect
 {
     public static readonly StyledProperty<double> RadiusProperty = AvaloniaProperty.Register<BlurEffect, double>(
         nameof(Radius), 5);
diff --git a/src/Avalonia.Base/Media/Effects/DropShadowEffect.cs b/src/Avalonia.Base/Media/Effects/DropShadowEffect.cs
index ea931c0a8c..835a142d8a 100644
--- a/src/Avalonia.Base/Media/Effects/DropShadowEffect.cs
+++ b/src/Avalonia.Base/Media/Effects/DropShadowEffect.cs
@@ -42,7 +42,7 @@ public abstract class DropShadowEffectBase : Effect
     }
 }
 
-public class DropShadowEffect : DropShadowEffectBase, IDropShadowEffect, IMutableEffect
+public sealed class DropShadowEffect : DropShadowEffectBase, IDropShadowEffect, IMutableEffect
 {
     public static readonly StyledProperty<double> OffsetXProperty = AvaloniaProperty.Register<DropShadowEffect, double>(
         nameof(OffsetX), 3.5355);
@@ -76,7 +76,7 @@ public class DropShadowEffect : DropShadowEffectBase, IDropShadowEffect, IMutabl
 /// <summary>
 /// This class is compatible with WPF's DropShadowEffect and provides Direction and ShadowDepth properties instead of OffsetX/OffsetY
 /// </summary>
-public class DropShadowDirectionEffect : DropShadowEffectBase, IDirectionDropShadowEffect, IMutableEffect
+public sealed class DropShadowDirectionEffect : DropShadowEffectBase, IDirectionDropShadowEffect, IMutableEffect
 {
     public static readonly StyledProperty<double> ShadowDepthProperty =
         AvaloniaProperty.Register<DropShadowDirectionEffect, double>(
diff --git a/src/Avalonia.Base/Media/Effects/Effect.cs b/src/Avalonia.Base/Media/Effects/Effect.cs
index 182e8613f8..abc1480d9d 100644
--- a/src/Avalonia.Base/Media/Effects/Effect.cs
+++ b/src/Avalonia.Base/Media/Effects/Effect.cs
@@ -90,4 +90,9 @@ public class Effect : Animatable, IAffectsRender
     {
         EffectAnimator.EnsureRegistered();
     }
+
+    internal Effect()
+    {
+        
+    }
 }
\ No newline at end of file
diff --git a/src/Avalonia.Base/Media/Effects/EffectAnimator.cs b/src/Avalonia.Base/Media/Effects/EffectAnimator.cs
index 70d359911b..8353afa6ab 100644
--- a/src/Avalonia.Base/Media/Effects/EffectAnimator.cs
+++ b/src/Avalonia.Base/Media/Effects/EffectAnimator.cs
@@ -7,7 +7,7 @@ using Avalonia.Media;
 // ReSharper disable once CheckNamespace
 namespace Avalonia.Animation.Animators;
 
-public class EffectAnimator : Animator<IEffect?>
+internal class EffectAnimator : Animator<IEffect?>
 {
     public override IDisposable? Apply(Animation animation, Animatable control, IClock? clock,
         IObservable<bool> match, Action? onComplete)
@@ -68,7 +68,7 @@ public class EffectAnimator : Animator<IEffect?>
     }
 }
 
-public abstract class EffectAnimatorBase<T> : Animator<IEffect?> where T : class, IEffect?
+internal abstract class EffectAnimatorBase<T> : Animator<IEffect?> where T : class, IEffect?
 {
     public override IDisposable BindAnimation(Animatable control, IObservable<IEffect?> instance)
     {
@@ -91,7 +91,7 @@ public abstract class EffectAnimatorBase<T> : Animator<IEffect?> where T : class
     }
 }
 
-public class BlurEffectAnimator : EffectAnimatorBase<IBlurEffect>
+internal class BlurEffectAnimator : EffectAnimatorBase<IBlurEffect>
 {
     private static readonly DoubleAnimator s_doubleAnimator = new DoubleAnimator();
 
@@ -102,7 +102,7 @@ public class BlurEffectAnimator : EffectAnimatorBase<IBlurEffect>
     }
 }
 
-public class DropShadowEffectAnimator : EffectAnimatorBase<IDropShadowEffect>
+internal class DropShadowEffectAnimator : EffectAnimatorBase<IDropShadowEffect>
 {
     private static readonly DoubleAnimator s_doubleAnimator = new DoubleAnimator();
 
diff --git a/src/Avalonia.Base/Media/Effects/EffectTransition.cs b/src/Avalonia.Base/Media/Effects/EffectTransition.cs
index b2e0d07355..d73d82fb2a 100644
--- a/src/Avalonia.Base/Media/Effects/EffectTransition.cs
+++ b/src/Avalonia.Base/Media/Effects/EffectTransition.cs
@@ -50,7 +50,7 @@ public class EffectTransition : Transition<IEffect?>
 
     }
 
-    public override IObservable<IEffect?> DoTransition(IObservable<double> progress, IEffect? oldValue, IEffect? newValue)
+    internal override IObservable<IEffect?> DoTransition(IObservable<double> progress, IEffect? oldValue, IEffect? newValue)
     {
         if ((oldValue != null || newValue != null)
             && (
diff --git a/src/Avalonia.Base/Media/GeometryDrawing.cs b/src/Avalonia.Base/Media/GeometryDrawing.cs
index dd359c5c64..3a768ac5ec 100644
--- a/src/Avalonia.Base/Media/GeometryDrawing.cs
+++ b/src/Avalonia.Base/Media/GeometryDrawing.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Media
     /// Represents a drawing operation that combines 
     /// a geometry with and brush and/or pen to produce rendered content.
     /// </summary>
-    public class GeometryDrawing : Drawing
+    public sealed class GeometryDrawing : Drawing
     {
         // Adding the Pen's stroke thickness here could yield wrong results due to transforms.
         private static readonly IPen s_boundsPen = new ImmutablePen(Colors.Black.ToUInt32(), 0);
diff --git a/src/Avalonia.Base/Media/GlyphRunDrawing.cs b/src/Avalonia.Base/Media/GlyphRunDrawing.cs
index 1bc56c3ff7..199809ccdc 100644
--- a/src/Avalonia.Base/Media/GlyphRunDrawing.cs
+++ b/src/Avalonia.Base/Media/GlyphRunDrawing.cs
@@ -1,6 +1,6 @@
 namespace Avalonia.Media
 {
-    public class GlyphRunDrawing : Drawing
+    public sealed class GlyphRunDrawing : Drawing
     {
         public static readonly StyledProperty<IBrush?> ForegroundProperty =
             AvaloniaProperty.Register<GlyphRunDrawing, IBrush?>(nameof(Foreground));
diff --git a/src/Avalonia.Base/Media/GradientBrush.cs b/src/Avalonia.Base/Media/GradientBrush.cs
index c2068a85ff..1c949c8f56 100644
--- a/src/Avalonia.Base/Media/GradientBrush.cs
+++ b/src/Avalonia.Base/Media/GradientBrush.cs
@@ -37,7 +37,7 @@ namespace Avalonia.Media
         /// </summary>
         [System.Diagnostics.CodeAnalysis.SuppressMessage("AvaloniaProperty", "AVP1012", 
             Justification = "Collection properties shouldn't be set with SetCurrentValue.")]
-        public GradientBrush()
+        internal GradientBrush()
         {
             this.GradientStops = new GradientStops();
         }
diff --git a/src/Avalonia.Base/Media/ImageBrush.cs b/src/Avalonia.Base/Media/ImageBrush.cs
index 48deffb79c..8c0ebb1e29 100644
--- a/src/Avalonia.Base/Media/ImageBrush.cs
+++ b/src/Avalonia.Base/Media/ImageBrush.cs
@@ -10,7 +10,7 @@ namespace Avalonia.Media
     /// <summary>
     /// Paints an area with an <see cref="IBitmap"/>.
     /// </summary>
-    public class ImageBrush : TileBrush, IImageBrush, IMutableBrush
+    public sealed class ImageBrush : TileBrush, IImageBrush, IMutableBrush
     {
         /// <summary>
         /// Defines the <see cref="Visual"/> property.
diff --git a/src/Avalonia.Base/Media/ImageDrawing.cs b/src/Avalonia.Base/Media/ImageDrawing.cs
index ad5e29e87d..ae737b0fb3 100644
--- a/src/Avalonia.Base/Media/ImageDrawing.cs
+++ b/src/Avalonia.Base/Media/ImageDrawing.cs
@@ -5,7 +5,7 @@ namespace Avalonia.Media
     /// <summary>
     /// Draws an image within a region defined by a <see cref="Rect"/>.
     /// </summary>
-    public class ImageDrawing : Drawing
+    public sealed class ImageDrawing : Drawing
     {
         /// <summary>
         /// Defines the <see cref="ImageSource"/> property.
diff --git a/src/Avalonia.Base/Media/MatrixTransform.cs b/src/Avalonia.Base/Media/MatrixTransform.cs
index 22f39b1ee2..01555b76f2 100644
--- a/src/Avalonia.Base/Media/MatrixTransform.cs
+++ b/src/Avalonia.Base/Media/MatrixTransform.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Media
     /// <summary>
     /// Transforms an <see cref="Visual"/> according to a <see cref="Matrix"/>.
     /// </summary>
-    public class MatrixTransform : Transform
+    public sealed class MatrixTransform : Transform
     {
         /// <summary>
         /// Defines the <see cref="Matrix"/> property.
diff --git a/src/Avalonia.Base/Media/MediaContext.Clock.cs b/src/Avalonia.Base/Media/MediaContext.Clock.cs
new file mode 100644
index 0000000000..dc2a39a822
--- /dev/null
+++ b/src/Avalonia.Base/Media/MediaContext.Clock.cs
@@ -0,0 +1,53 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using Avalonia.Animation;
+using Avalonia.Reactive;
+using Avalonia.Threading;
+
+namespace Avalonia.Media;
+
+internal partial class MediaContext
+{
+    private readonly MediaContextClock _clock;
+    public IGlobalClock Clock => _clock;
+    private readonly Stopwatch _time = Stopwatch.StartNew();
+    
+    class MediaContextClock : IGlobalClock
+    {
+        private readonly MediaContext _parent;
+        private List<IObserver<TimeSpan>> _observers = new();
+        public bool HasNewSubscriptions { get; set; }
+        public bool HasSubscriptions => _observers.Count > 0;
+
+        public MediaContextClock(MediaContext parent)
+        {
+            _parent = parent;
+        }
+
+        public IDisposable Subscribe(IObserver<TimeSpan> observer)
+        {
+            _parent.ScheduleRender(false);
+            Dispatcher.UIThread.VerifyAccess();
+            HasNewSubscriptions = true;
+            _observers.Add(observer);
+            return Disposable.Create(() =>
+            {
+                Dispatcher.UIThread.VerifyAccess();
+                _observers.Remove(observer);
+            });
+        }
+
+        public void Pulse(TimeSpan now)
+        {
+            foreach (var observer in _observers.ToArray())
+                observer.OnNext(now);
+        }
+
+        public PlayState PlayState
+        {
+            get => PlayState.Run;
+            set => throw new InvalidOperationException();
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/Avalonia.Base/Media/MediaContext.Compositor.cs b/src/Avalonia.Base/Media/MediaContext.Compositor.cs
new file mode 100644
index 0000000000..9bdd77960d
--- /dev/null
+++ b/src/Avalonia.Base/Media/MediaContext.Compositor.cs
@@ -0,0 +1,149 @@
+using System;
+using System.Threading.Tasks;
+using Avalonia.Platform;
+using Avalonia.Rendering.Composition;
+using Avalonia.Rendering.Composition.Transport;
+using Avalonia.Threading;
+
+namespace Avalonia.Media;
+
+partial class MediaContext
+{
+    private bool _scheduleCommitOnLastCompositionBatchCompletion;
+    
+    /// <summary>
+    /// Actually sends the current batch to the compositor and does the required housekeeping
+    /// This is the only place that should be allowed to call Commit
+    /// </summary>
+    private Batch CommitCompositor(Compositor compositor)
+    {
+        var commit = compositor.Commit();
+        _requestedCommits.Remove(compositor);
+        _pendingCompositionBatches[compositor] = commit;
+        commit.Processed.ContinueWith(_ =>
+            Dispatcher.UIThread.Post(() => CompositionBatchFinished(compositor, commit), DispatcherPriority.Send));
+        return commit;
+    }
+    
+    /// <summary>
+    /// Handles batch completion, required to re-schedule a render pass if one was skipped due to compositor throttling
+    /// </summary>
+    private void CompositionBatchFinished(Compositor compositor, Batch batch)
+    {
+        // Check if it was the last commited batch, since sometimes we are forced to send a new
+        // one without waiting for the previous one to complete  
+        if (_pendingCompositionBatches.TryGetValue(compositor, out var waitingForBatch) && waitingForBatch == batch)
+            _pendingCompositionBatches.Remove(compositor);
+
+        if (_pendingCompositionBatches.Count == 0)
+        {
+            _animationsAreWaitingForComposition = false;
+
+            // Check if we have uncommited changes
+            if (_scheduleCommitOnLastCompositionBatchCompletion)
+            {
+                _scheduleCommitOnLastCompositionBatchCompletion = false;
+                if (!CommitCompositorsWithThrottling())
+                    ScheduleRenderForAnimationsIfNeeded();
+
+            }
+            // Check if there are active animations and schedule the next render
+            else
+                ScheduleRenderForAnimationsIfNeeded();
+        }
+    }
+
+    void ScheduleRenderForAnimationsIfNeeded()
+    {
+        if (_clock.HasSubscriptions) 
+            ScheduleRender(false);
+    }
+
+    /// <summary>
+    /// Triggers a composition commit if any batches are waiting to be sent,
+    /// handles throttling
+    /// </summary>
+    /// <returns>true if there are pending commits in-flight and there will be a "all-done" callback later</returns>
+    private bool CommitCompositorsWithThrottling()
+    {
+        // Check if we are still waiting for previous composition batches
+        if (_pendingCompositionBatches.Count > 0)
+        {
+            _scheduleCommitOnLastCompositionBatchCompletion = true;
+            // Previous commit isn't handled yet
+            return true;
+        }
+        
+        if (_requestedCommits.Count == 0)
+            // Nothing to do, and there are no pending commits
+            return false;
+        
+        foreach (var c in _requestedCommits)
+            CommitCompositor(c);
+        
+        _requestedCommits.Clear();
+        return true;
+    }
+    
+    /// <summary>
+    /// Executes a synchronous commit when we need to wait for composition jobs to be done
+    /// Is used in resize and TopLevel destruction scenarios
+    /// </summary>
+    private void SyncCommit(Compositor compositor, bool waitFullRender)
+    {
+        // Unit tests are assuming that they can call any API without setting up platforms
+        if (AvaloniaLocator.Current.GetService<IPlatformRenderInterface>() == null)
+            return;
+        
+        if (compositor is
+            {
+                UseUiThreadForSynchronousCommits: false,
+                Loop.RunsInBackground: true
+            })
+        {
+            var batch = CommitCompositor(compositor);
+            (waitFullRender ? batch.Rendered : batch.Processed).Wait();
+        }
+        else
+        {
+            CommitCompositor(compositor);
+            compositor.Server.Render();
+        }
+    }
+    
+    /// <summary>
+    /// This method handles synchronous rendering of a surface when requested by the OS (typically during the resize)
+    /// </summary>
+    // TODO: do we need to execute a render pass here too?
+    // We've previously tried that and it made the resize experience worse
+    public void ImmediateRenderRequested(CompositionTarget target)
+    {
+        SyncCommit(target.Compositor, true);
+    }
+
+
+    /// <summary>
+    /// This method handles synchronous destruction of the composition target, so we are guaranteed
+    /// to release all resources when a TopLevel is being destroyed 
+    /// </summary>
+    public void SyncDisposeCompositionTarget(CompositionTarget compositionTarget)
+    {
+        compositionTarget.Dispose();
+        
+        // TODO: introduce a way to skip any actual rendering for other targets and only do a dispose?
+        SyncCommit(compositionTarget.Compositor, false);
+    }
+    
+    /// <summary>
+    /// This method schedules a render when something has called RequestCommitAsync
+    /// This can be triggered by user code outside of our normal layout and rendering
+    /// </summary>
+    void ICompositorScheduler.CommitRequested(Compositor compositor)
+    {
+        if(!_requestedCommits.Add(compositor))
+            return;
+
+        // TODO: maybe skip the full render here?
+        ScheduleRender(true);
+    }
+}
\ No newline at end of file
diff --git a/src/Avalonia.Base/Media/MediaContext.cs b/src/Avalonia.Base/Media/MediaContext.cs
new file mode 100644
index 0000000000..c261dd80b8
--- /dev/null
+++ b/src/Avalonia.Base/Media/MediaContext.cs
@@ -0,0 +1,227 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using Avalonia.Animation;
+using Avalonia.Layout;
+using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
+using Avalonia.Rendering.Composition.Transport;
+using Avalonia.Threading;
+
+namespace Avalonia.Media;
+
+internal partial class MediaContext : ICompositorScheduler
+{
+    private DispatcherOperation? _nextRenderOp;
+    private DispatcherOperation? _inputMarkerOp;
+    private TimeSpan _inputMarkerAddedAt;
+    private bool _isRendering;
+    private bool _animationsAreWaitingForComposition;
+    private const double MaxSecondsWithoutInput = 1;
+    private readonly Action _render;
+    private readonly Action _inputMarkerHandler;
+    private readonly HashSet<Compositor> _requestedCommits = new();
+    private readonly Dictionary<Compositor, Batch> _pendingCompositionBatches = new();
+    private record  TopLevelInfo(Compositor Compositor, CompositingRenderer Renderer, ILayoutManager LayoutManager);
+
+    private List<Action>? _invokeOnRenderCallbacks;
+    private readonly Stack<List<Action>> _invokeOnRenderCallbackListPool = new();
+
+    private DispatcherTimer _animationsTimer = new(DispatcherPriority.Render)
+    {
+        // Since this timer is used to drive animations that didn't contribute to the previous frame at all
+        // We can safely use 16ms interval until we fix our animation system to actually report the next expected 
+        // frame
+        Interval = TimeSpan.FromMilliseconds(16)
+    };
+
+    private Dictionary<object, TopLevelInfo> _topLevels = new();
+
+    private MediaContext()
+    {
+        _render = Render;
+        _inputMarkerHandler = InputMarkerHandler;
+        _clock = new(this);
+        _animationsTimer.Tick += (_, _) =>
+        {
+            _animationsTimer.Stop();
+            ScheduleRender(false);
+        };
+    }
+    
+    public static MediaContext Instance
+    {
+        get
+        {
+            // Technically it's supposed to be a thread-static singleton, but we don't have multiple threads
+            // and need to do a full reset for unit tests
+            var context = AvaloniaLocator.Current.GetService<MediaContext>();
+            if (context == null)
+                AvaloniaLocator.CurrentMutable.Bind<MediaContext>().ToConstant(context = new());
+            return context;
+        }
+    }
+    
+    /// <summary>
+    /// Schedules the next render operation, handles render throttling for input processing
+    /// </summary>
+    private void ScheduleRender(bool now)
+    {
+        // Already scheduled, nothing to do
+        if (_nextRenderOp != null)
+        {
+            if (now)
+                _nextRenderOp.Priority = DispatcherPriority.Render;
+            return;
+        }
+        // Sometimes our animation, layout and render passes might be taking more than a frame to complete
+        // which can cause a "freeze"-like state when UI is being updated, but input is never being processed
+        // So here we inject an operation with Input priority to check if Input wasn't being processed
+        // for a long time. If that's the case the next rendering operation will be scheduled to happen after all pending input
+        
+        var priority = DispatcherPriority.Render;
+        
+        if (_inputMarkerOp == null)
+        {
+            _inputMarkerOp = Dispatcher.UIThread.InvokeAsync(_inputMarkerHandler, DispatcherPriority.Input);
+            _inputMarkerAddedAt = _time.Elapsed;
+        }
+        else if (!now && (_time.Elapsed - _inputMarkerAddedAt).TotalSeconds > MaxSecondsWithoutInput)
+        {
+            priority = DispatcherPriority.Input;
+        }
+        
+
+        _nextRenderOp = Dispatcher.UIThread.InvokeAsync(_render, priority);
+    }
+    
+    /// <summary>
+    /// This handles the _inputMarkerOp message.  We're using
+    /// _inputMarkerOp to determine if input priority dispatcher ops
+    /// have been processes.
+    /// </summary>
+    private void InputMarkerHandler()
+    {
+        //set the marker to null so we know that input priority has been processed
+        _inputMarkerOp = null;
+    }
+
+    private void Render()
+    {
+        try
+        {
+            _isRendering = true;
+            RenderCore();
+        }
+        finally
+        {
+            _nextRenderOp = null;
+            _isRendering = false;
+        }
+    }
+    
+    private void RenderCore()
+    {
+        var now = _time.Elapsed;
+        if (!_animationsAreWaitingForComposition)
+            _clock.Pulse(now);
+
+        // Since new animations could be started during the layout and can affect layout/render
+        // We are doing several iterations when it happens
+        for (var c = 0; c < 10; c++)
+        {
+            _clock.HasNewSubscriptions = false;
+            FireInvokeOnRenderCallbacks();
+            
+            if (_clock.HasNewSubscriptions)
+            {
+                _clock.Pulse(now);
+                continue;
+            }
+
+            break;
+        }
+        
+        if (_requestedCommits.Count > 0 || _clock.HasSubscriptions)
+        {
+            _animationsAreWaitingForComposition = CommitCompositorsWithThrottling();
+            if (!_animationsAreWaitingForComposition && _clock.HasSubscriptions) 
+                _animationsTimer.Start();
+        }
+    }
+
+    // Used for unit tests
+    public bool IsTopLevelActive(object key) => _topLevels.ContainsKey(key);
+
+    public void AddTopLevel(object key, ILayoutManager layoutManager, IRenderer renderer)
+    {
+        if(_topLevels.ContainsKey(key))
+            return;
+        var render = (CompositingRenderer)renderer;
+        _topLevels.Add(key, new TopLevelInfo(render.Compositor, render, layoutManager));
+        render.Start();
+        ScheduleRender(true);
+    }
+
+    public void RemoveTopLevel(object key)
+    {
+        if (_topLevels.TryGetValue(key, out var info))
+        {
+            _topLevels.Remove(key);
+            info.Renderer.Stop();
+        }
+    }
+
+    /// <summary>
+    /// Calls all _invokeOnRenderCallbacks until no more are added
+    /// </summary>
+    private void FireInvokeOnRenderCallbacks()
+    {
+        int callbackLoopCount = 0;
+        int count = _invokeOnRenderCallbacks?.Count ?? 0;
+
+        // This outer loop is to re-run layout in case the app causes a layout to get enqueued in response
+        // to a Loaded event. In this case we would like to re-run layout before we allow render.
+        do
+        {
+            while (count > 0)
+            {
+                callbackLoopCount++;
+                if (callbackLoopCount > 153)
+                    throw new InvalidOperationException("Infinite layout loop detected");
+
+                var callbacks = _invokeOnRenderCallbacks!;
+                _invokeOnRenderCallbacks = null;
+
+                for (int i = 0; i < count; i++) 
+                    callbacks[i].Invoke();
+                
+                callbacks.Clear();
+                _invokeOnRenderCallbackListPool.Push(callbacks);
+
+                count = _invokeOnRenderCallbacks?.Count ?? 0;
+            }
+
+            // TODO: port the rest of the Loaded logic later
+            // Fire all the pending Loaded events before Render happens
+            // but after the layout storm has subsided
+            // FireLoadedPendingCallbacks();
+
+            count =  _invokeOnRenderCallbacks?.Count ?? 0;
+        }
+        while (count > 0);
+    }
+    
+    public void BeginInvokeOnRender(Action callback)
+    {
+        if (_invokeOnRenderCallbacks == null)
+            _invokeOnRenderCallbacks =
+                _invokeOnRenderCallbackListPool.Count > 0 ? _invokeOnRenderCallbackListPool.Pop() : new();
+        
+        _invokeOnRenderCallbacks.Add(callback);
+
+        if (!_isRendering) 
+            ScheduleRender(true);
+    }
+}
\ No newline at end of file
diff --git a/src/Avalonia.Base/Media/PlatformDrawingContext.cs b/src/Avalonia.Base/Media/PlatformDrawingContext.cs
index 1c1f202532..b81582f845 100644
--- a/src/Avalonia.Base/Media/PlatformDrawingContext.cs
+++ b/src/Avalonia.Base/Media/PlatformDrawingContext.cs
@@ -76,8 +76,8 @@ internal sealed class PlatformDrawingContext : DrawingContext
     protected override void PushGeometryClipCore(Geometry clip) =>
         _impl.PushGeometryClip(clip.PlatformImpl ?? throw new ArgumentException());
 
-    protected override void PushOpacityCore(double opacity, Rect bounds) => 
-        _impl.PushOpacity(opacity, bounds);
+    protected override void PushOpacityCore(double opacity) => 
+        _impl.PushOpacity(opacity, null);
 
     protected override void PushOpacityMaskCore(IBrush mask, Rect bounds) =>
         _impl.PushOpacityMask(mask, bounds);
diff --git a/src/Avalonia.Base/Media/RotateTransform.cs b/src/Avalonia.Base/Media/RotateTransform.cs
index ab3ea6770f..b02a111939 100644
--- a/src/Avalonia.Base/Media/RotateTransform.cs
+++ b/src/Avalonia.Base/Media/RotateTransform.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Media
     /// <summary>
     /// Rotates an <see cref="Visual"/>.
     /// </summary>
-    public class RotateTransform : Transform
+    public sealed class RotateTransform : Transform
     {
         /// <summary>
         /// Defines the <see cref="Angle"/> property.
diff --git a/src/Avalonia.Base/Media/ScaleTransform.cs b/src/Avalonia.Base/Media/ScaleTransform.cs
index fca2f4bf2a..6aac15f604 100644
--- a/src/Avalonia.Base/Media/ScaleTransform.cs
+++ b/src/Avalonia.Base/Media/ScaleTransform.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Media
     /// <summary>
     /// Scale an <see cref="Visual"/>.
     /// </summary>
-    public class ScaleTransform : Transform
+    public sealed class ScaleTransform : Transform
     {
         /// <summary>
         /// Defines the <see cref="ScaleX"/> property.
diff --git a/src/Avalonia.Base/Media/SkewTransform.cs b/src/Avalonia.Base/Media/SkewTransform.cs
index d268bee778..2019f24444 100644
--- a/src/Avalonia.Base/Media/SkewTransform.cs
+++ b/src/Avalonia.Base/Media/SkewTransform.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Media
     /// <summary>
     /// Skews an <see cref="Visual"/>.
     /// </summary>
-    public class SkewTransform : Transform
+    public sealed class SkewTransform : Transform
     {
         /// <summary>
         /// Defines the <see cref="AngleX"/> property.
diff --git a/src/Avalonia.Base/Media/SolidColorBrush.cs b/src/Avalonia.Base/Media/SolidColorBrush.cs
index a552e262ae..4ba60e9506 100644
--- a/src/Avalonia.Base/Media/SolidColorBrush.cs
+++ b/src/Avalonia.Base/Media/SolidColorBrush.cs
@@ -10,7 +10,7 @@ namespace Avalonia.Media
     /// <summary>
     /// Fills an area with a solid color.
     /// </summary>
-    public class SolidColorBrush : Brush, ISolidColorBrush, IMutableBrush
+    public sealed class SolidColorBrush : Brush, ISolidColorBrush, IMutableBrush
     {
         /// <summary>
         /// Defines the <see cref="Color"/> property.
diff --git a/src/Avalonia.Base/Media/TextFormatting/BidiReorderer.cs b/src/Avalonia.Base/Media/TextFormatting/BidiReorderer.cs
index 4db55fae6d..39ef8cce48 100644
--- a/src/Avalonia.Base/Media/TextFormatting/BidiReorderer.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/BidiReorderer.cs
@@ -18,14 +18,14 @@ namespace Avalonia.Media.TextFormatting
         public static BidiReorderer Instance
             => t_instance ??= new();
 
-        public void BidiReorder(Span<TextRun> textRuns, FlowDirection flowDirection)
+        public IndexedTextRun[] BidiReorder(Span<TextRun> textRuns, FlowDirection flowDirection, int firstTextSourceIndex)
         {
             Debug.Assert(_runs.Length == 0);
             Debug.Assert(_ranges.Length == 0);
 
             if (textRuns.IsEmpty)
             {
-                return;
+                return Array.Empty<IndexedTextRun>();
             }
 
             try
@@ -46,6 +46,22 @@ namespace Avalonia.Media.TextFormatting
 
                 // Reorder them into visual order.
                 var firstIndex = LinearReorder();
+                var indexedTextRuns = new IndexedTextRun[textRuns.Length];
+
+                for (var i = 0; i < textRuns.Length; i++)
+                {
+                    var currentRun = textRuns[i];
+
+                    indexedTextRuns[i] = new IndexedTextRun
+                    {
+                        TextRun = currentRun,
+                        TextSourceCharacterIndex = firstTextSourceIndex,
+                        RunIndex = i,
+                        NextRunIndex = i + 1
+                    };
+
+                    firstTextSourceIndex += currentRun.Length;
+                }
 
                 // Now perform a recursive reversal of each run.
                 // From the highest level found in the text to the lowest odd level on each line, including intermediate levels
@@ -76,7 +92,7 @@ namespace Avalonia.Media.TextFormatting
                 if (max == 0 || (min == max && (max & 1) == 0))
                 {
                     // Nothing to reverse.
-                    return;
+                    return indexedTextRuns;
                 }
 
                 // Now apply the reversal and replace the original contents.
@@ -107,13 +123,25 @@ namespace Avalonia.Media.TextFormatting
                 var index = 0;
 
                 currentIndex = firstIndex;
+
                 while (currentIndex >= 0)
                 {
                     ref var current = ref _runs[currentIndex];
-                    textRuns[index++] = current.Run;
+
+                    textRuns[index] = current.Run;
+
+                    var indexedRun = indexedTextRuns[index];
+
+                    indexedRun.RunIndex = current.RunIndex;
+
+                    indexedRun.NextRunIndex = current.NextRunIndex;
+
+                    index++;
 
                     currentIndex = current.NextRunIndex;
                 }
+
+                return indexedTextRuns;
             }
             finally
             {
@@ -227,25 +255,6 @@ namespace Avalonia.Media.TextFormatting
             return previousIndex;
         }
 
-        private struct OrderedBidiRun
-        {
-            public OrderedBidiRun(int runIndex, TextRun run, sbyte level)
-            {
-                RunIndex = runIndex;
-                Run = run;
-                Level = level;
-                NextRunIndex = -1;
-            }
-
-            public int RunIndex { get; }
-
-            public sbyte Level { get; }
-
-            public TextRun Run { get; }
-
-            public int NextRunIndex { get; set; } // -1 if none
-        }
-
         private struct BidiRange
         {
             public BidiRange(sbyte level, int leftRunIndex, int rightRunIndex, int previousRangeIndex)
@@ -265,4 +274,23 @@ namespace Avalonia.Media.TextFormatting
             public int PreviousRangeIndex { get; } // -1 if none
         }
     }
+
+    internal struct OrderedBidiRun
+    {
+        public OrderedBidiRun(int runIndex, TextRun run, sbyte level)
+        {
+            RunIndex = runIndex;
+            Run = run;
+            Level = level;
+            NextRunIndex = -1;
+        }
+
+        public int RunIndex { get; }
+
+        public sbyte Level { get; }
+
+        public TextRun Run { get; }
+
+        public int NextRunIndex { get; set; } // -1 if none
+    }
 }
diff --git a/src/Avalonia.Base/Media/TextFormatting/IndexedTextRun.cs b/src/Avalonia.Base/Media/TextFormatting/IndexedTextRun.cs
new file mode 100644
index 0000000000..0eb98533d2
--- /dev/null
+++ b/src/Avalonia.Base/Media/TextFormatting/IndexedTextRun.cs
@@ -0,0 +1,10 @@
+namespace Avalonia.Media.TextFormatting
+{
+    internal class IndexedTextRun
+    {
+        public int TextSourceCharacterIndex { get; init; }
+        public int RunIndex { get; set; }
+        public int NextRunIndex { get; set; }
+        public TextRun? TextRun { get; init; }
+    }
+}
diff --git a/src/Avalonia.Base/Media/TextFormatting/TextBounds.cs b/src/Avalonia.Base/Media/TextFormatting/TextBounds.cs
index 93edf68348..946c2e6931 100644
--- a/src/Avalonia.Base/Media/TextFormatting/TextBounds.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/TextBounds.cs
@@ -1,4 +1,5 @@
 using System.Collections.Generic;
+using System.Diagnostics;
 
 namespace Avalonia.Media.TextFormatting
 {
@@ -10,6 +11,7 @@ namespace Avalonia.Media.TextFormatting
         /// <summary>
         /// Constructing TextBounds object
         /// </summary>
+        [DebuggerStepThrough]
         internal TextBounds(Rect bounds, FlowDirection flowDirection, IList<TextRunBounds> runBounds)
         {
             Rectangle = bounds;
diff --git a/src/Avalonia.Base/Media/TextFormatting/TextLayout.cs b/src/Avalonia.Base/Media/TextFormatting/TextLayout.cs
index 0697831987..4ccb3f6a37 100644
--- a/src/Avalonia.Base/Media/TextFormatting/TextLayout.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/TextLayout.cs
@@ -60,14 +60,10 @@ namespace Avalonia.Media.TextFormatting
 
             _textTrimming = textTrimming ?? TextTrimming.None;
 
-            LineHeight = lineHeight;
-
             MaxWidth = maxWidth;
 
             MaxHeight = maxHeight;
 
-            LetterSpacing = letterSpacing;
-
             MaxLines = maxLines;
 
             _textLines = CreateTextLines();
@@ -81,8 +77,6 @@ namespace Avalonia.Media.TextFormatting
         /// <param name="textTrimming">The text trimming.</param>
         /// <param name="maxWidth">The maximum width.</param>
         /// <param name="maxHeight">The maximum height.</param>
-        /// <param name="lineHeight">The height of each line of text.</param>
-        /// <param name="letterSpacing">The letter spacing that is applied to rendered glyphs.</param>
         /// <param name="maxLines">The maximum number of text lines.</param>
         public TextLayout(
             ITextSource textSource,
@@ -90,8 +84,6 @@ namespace Avalonia.Media.TextFormatting
             TextTrimming? textTrimming = null,
             double maxWidth = double.PositiveInfinity,
             double maxHeight = double.PositiveInfinity,
-            double lineHeight = double.NaN,
-            double letterSpacing = 0,
             int maxLines = 0)
         {
             _textSource = textSource;
@@ -100,14 +92,10 @@ namespace Avalonia.Media.TextFormatting
 
             _textTrimming = textTrimming ?? TextTrimming.None;
 
-            LineHeight = lineHeight;
-
             MaxWidth = maxWidth;
 
             MaxHeight = maxHeight;
 
-            LetterSpacing = letterSpacing;
-
             MaxLines = maxLines;
 
             _textLines = CreateTextLines();
@@ -120,7 +108,7 @@ namespace Avalonia.Media.TextFormatting
         /// A value of NaN (equivalent to an attribute value of "Auto") indicates that the line height
         /// is determined automatically from the current font characteristics. The default is NaN.
         /// </remarks>
-        public double LineHeight { get; }
+        public double LineHeight => _paragraphProperties.LineHeight;
 
         /// <summary>
         /// Gets the maximum width.
@@ -140,7 +128,7 @@ namespace Avalonia.Media.TextFormatting
         /// <summary>
         /// Gets the text spacing.
         /// </summary>
-        public double LetterSpacing { get; }
+        public double LetterSpacing  => _paragraphProperties.LetterSpacing;
 
         /// <summary>
         /// Gets the text lines.
@@ -495,7 +483,7 @@ namespace Avalonia.Media.TextFormatting
         /// <param name="lineHeight">The height of each line of text.</param>
         /// <param name="letterSpacing">The letter spacing that is applied to rendered glyphs.</param>
         /// <returns></returns>
-        private static TextParagraphProperties CreateTextParagraphProperties(Typeface typeface, double fontSize,
+        internal static TextParagraphProperties CreateTextParagraphProperties(Typeface typeface, double fontSize,
             IBrush? foreground, TextAlignment textAlignment, TextWrapping textWrapping,
             TextDecorationCollection? textDecorations, FlowDirection flowDirection, double lineHeight,
             double letterSpacing)
diff --git a/src/Avalonia.Base/Media/TextFormatting/TextLineImpl.cs b/src/Avalonia.Base/Media/TextFormatting/TextLineImpl.cs
index a0d7cabefd..c2ec78e187 100644
--- a/src/Avalonia.Base/Media/TextFormatting/TextLineImpl.cs
+++ b/src/Avalonia.Base/Media/TextFormatting/TextLineImpl.cs
@@ -4,8 +4,12 @@ using Avalonia.Utilities;
 
 namespace Avalonia.Media.TextFormatting
 {
-    internal sealed class TextLineImpl : TextLine
+    internal class TextLineImpl : TextLine
     {
+        internal static Comparer<TextBounds> TextBoundsComparer { get; } =
+            Comparer<TextBounds>.Create((x, y) => x.Rectangle.Left.CompareTo(y.Rectangle.Left));
+
+        private IReadOnlyList<IndexedTextRun>? _indexedTextRuns;
         private readonly TextRun[] _textRuns;
         private readonly double _paragraphWidth;
         private readonly TextParagraphProperties _paragraphProperties;
@@ -338,184 +342,169 @@ namespace Avalonia.Media.TextFormatting
         /// <inheritdoc/>
         public override double GetDistanceFromCharacterHit(CharacterHit characterHit)
         {
-            var flowDirection = _paragraphProperties.FlowDirection;
-            var characterIndex = characterHit.FirstCharacterIndex + characterHit.TrailingLength;
-            var currentPosition = FirstTextSourceIndex;
-            var remainingLength = characterIndex - FirstTextSourceIndex;
-
-            var currentDistance = Start;
-
-            if (flowDirection == FlowDirection.LeftToRight)
+            if (_indexedTextRuns is null || _indexedTextRuns.Count == 0)
             {
-                for (var index = 0; index < _textRuns.Length; index++)
-                {
-                    var currentRun = _textRuns[index];
-
-                    if (currentRun is ShapedTextRun shapedRun && !shapedRun.ShapedBuffer.IsLeftToRight)
-                    {
-                        var i = index;
-
-                        var rightToLeftWidth = shapedRun.Size.Width;
-
-                        while (i + 1 <= _textRuns.Length - 1)
-                        {
-                            var nextRun = _textRuns[i + 1];
-
-                            if (nextRun is ShapedTextRun nextShapedRun && !nextShapedRun.ShapedBuffer.IsLeftToRight)
-                            {
-                                i++;
+                return Start;
+            }
 
-                                rightToLeftWidth += nextShapedRun.Size.Width;
+            var characterIndex = Math.Min(
+            characterHit.FirstCharacterIndex + characterHit.TrailingLength,
+            FirstTextSourceIndex + Length);
 
-                                continue;
-                            }
+            var currentPosition = FirstTextSourceIndex;
 
-                            break;
-                        }
+            static FlowDirection GetDirection(TextRun textRun, FlowDirection currentDirection)
+            {
+                if (textRun is ShapedTextRun shapedTextRun)
+                {
+                    return shapedTextRun.ShapedBuffer.IsLeftToRight ?
+                        FlowDirection.LeftToRight :
+                        FlowDirection.RightToLeft;
+                }
 
-                        if (i > index)
-                        {
-                            while (i >= index)
-                            {
-                                currentRun = _textRuns[i];
+                return currentDirection;
+            }
 
-                                if (currentRun is DrawableTextRun drawable)
-                                {
-                                    rightToLeftWidth -= drawable.Size.Width;
-                                }
+            IndexedTextRun FindIndexedRun()
+            {
+                var i = 0;
 
-                                if (currentPosition + currentRun.Length >= characterIndex)
-                                {
-                                    break;
-                                }
+                IndexedTextRun currentIndexedRun = _indexedTextRuns[i];
 
-                                currentPosition += currentRun.Length;
+                while(currentIndexedRun.TextSourceCharacterIndex != currentPosition)
+                {
+                    if(i + 1 < _indexedTextRuns.Count)
+                    {
+                        i++;
 
-                                remainingLength -= currentRun.Length;
+                        currentIndexedRun = _indexedTextRuns[i];
+                    }
+                }
 
-                                i--;
-                            }
+                return currentIndexedRun;
+            }
 
-                            currentDistance += rightToLeftWidth;
-                        }
-                    }
+            double GetPreceedingDistance(int firstIndex)
+            {
+                var distance = 0.0;
 
-                    if (currentPosition + currentRun.Length >= characterIndex &&
-                        TryGetDistanceFromCharacterHit(currentRun, characterHit, currentPosition, remainingLength, flowDirection, out var distance, out _))
-                    {
-                        return Math.Max(0, currentDistance + distance);
-                    }
+                for (var i = 0; i < firstIndex; i++)
+                {
+                    var currentRun = _textRuns[i];
 
                     if (currentRun is DrawableTextRun drawableTextRun)
                     {
-                        currentDistance += drawableTextRun.Size.Width;
+                        distance += drawableTextRun.Size.Width;
                     }
-
-                    //No hit hit found so we add the full width
-
-                    currentPosition += currentRun.Length;
-                    remainingLength -= currentRun.Length;
                 }
+
+                return distance;
             }
-            else
+
+            TextRun? currentTextRun = null;
+            var currentIndexedRun = FindIndexedRun();
+
+            while (currentPosition < FirstTextSourceIndex + Length)
             {
-                currentDistance += WidthIncludingTrailingWhitespace;
+                currentTextRun = currentIndexedRun.TextRun;
 
-                for (var index = _textRuns.Length - 1; index >= 0; index--)
+                if (currentTextRun == null)
                 {
-                    var currentRun = _textRuns[index];
+                    break;
+                }
 
-                    if (TryGetDistanceFromCharacterHit(currentRun, characterHit, currentPosition, remainingLength,
-                        flowDirection, out var distance, out var currentGlyphRun))
+                if (currentIndexedRun.TextSourceCharacterIndex + currentTextRun.Length <= characterHit.FirstCharacterIndex)
+                {
+                    if (currentPosition + currentTextRun.Length < FirstTextSourceIndex + Length)
                     {
-                        if (currentGlyphRun != null)
-                        {
-                            currentDistance -= currentGlyphRun.Bounds.Width;
-                        }
+                        currentPosition += currentTextRun.Length;
 
-                        return currentDistance + distance;
-                    }
+                        currentIndexedRun = FindIndexedRun();
 
-                    if (currentRun is DrawableTextRun drawableTextRun)
-                    {
-                        currentDistance -= drawableTextRun.Size.Width;
+                        continue;
                     }
-
-                    //No hit hit found so we add the full width
-                    currentPosition += currentRun.Length;
-                    remainingLength -= currentRun.Length;
                 }
+
+                break;
             }
 
-            return Math.Max(0, currentDistance);
-        }
+            if (currentTextRun == null)
+            {
+                return 0;
+            }
 
-        private static bool TryGetDistanceFromCharacterHit(
-            TextRun currentRun,
-            CharacterHit characterHit,
-            int currentPosition,
-            int remainingLength,
-            FlowDirection flowDirection,
-            out double distance,
-            out GlyphRun? currentGlyphRun)
-        {
-            var characterIndex = characterHit.FirstCharacterIndex + characterHit.TrailingLength;
-            var isTrailingHit = characterHit.TrailingLength > 0;
+            var directionalWidth = 0.0;
+            var firstRunIndex = currentIndexedRun.RunIndex;
+            var lastRunIndex = firstRunIndex;
 
-            distance = 0;
-            currentGlyphRun = null;
+            var currentDirection = GetDirection(currentTextRun, _resolvedFlowDirection);
 
-            switch (currentRun)
+            var currentX = Start + GetPreceedingDistance(currentIndexedRun.RunIndex);
+
+            if (currentTextRun is DrawableTextRun currentDrawable)
             {
-                case ShapedTextRun shapedTextCharacters:
-                    {
-                        currentGlyphRun = shapedTextCharacters.GlyphRun;
+                directionalWidth = currentDrawable.Size.Width;
+            }
 
-                        if (currentPosition + remainingLength <= currentPosition + currentRun.Length)
-                        {
-                            characterHit = new CharacterHit(currentPosition + remainingLength);
+            if (currentTextRun is not TextEndOfLine)
+            {
+                if (currentDirection == FlowDirection.LeftToRight)
+                {
+                    // Find consecutive runs of same direction
+                    for (; lastRunIndex + 1 < _textRuns.Length; lastRunIndex++)
+                    {
+                        var nextRun = _textRuns[lastRunIndex + 1];
 
-                            distance = currentGlyphRun.GetDistanceFromCharacterHit(characterHit);
+                        var nextDirection = GetDirection(nextRun, currentDirection);
 
-                            return true;
+                        if (currentDirection != nextDirection)
+                        {
+                            break;
                         }
 
-                        if (currentPosition + remainingLength == currentPosition + currentRun.Length && isTrailingHit)
+                        if (nextRun is DrawableTextRun nextDrawable)
                         {
-                            if (currentGlyphRun.IsLeftToRight || flowDirection == FlowDirection.RightToLeft)
-                            {
-                                distance = currentGlyphRun.Bounds.Width;
-                            }
-
-                            return true;
+                            directionalWidth += nextDrawable.Size.Width;
                         }
-
-                        break;
                     }
-                case DrawableTextRun drawableTextRun:
+                }
+                else
+                {
+                    // Find consecutive runs of same direction
+                    for (; firstRunIndex - 1 > 0; firstRunIndex--)
                     {
-                        if (characterIndex == currentPosition)
+                        var previousRun = _textRuns[firstRunIndex - 1];
+
+                        var previousDirection = GetDirection(previousRun, currentDirection);
+
+                        if (currentDirection != previousDirection)
                         {
-                            return true;
+                            break;
                         }
 
-                        if (characterIndex == currentPosition + currentRun.Length)
+                        if (previousRun is DrawableTextRun previousDrawable)
                         {
-                            distance = drawableTextRun.Size.Width;
-
-                            return true;
+                            directionalWidth += previousDrawable.Size.Width;
 
+                            currentX -= previousDrawable.Size.Width;
                         }
+                    }
+                }
+            }
 
-                        break;
+            switch (currentDirection)
+            {
+                case FlowDirection.RightToLeft:
+                    {
+                        return GetTextRunBoundsRightToLeft(firstRunIndex, lastRunIndex, currentX + directionalWidth, characterIndex,
+                                currentPosition, 1, out _, out _).Rectangle.Right;
                     }
                 default:
                     {
-                        return false;
+                        return GetTextBoundsLeftToRight(firstRunIndex, lastRunIndex, currentX, characterIndex,
+                                currentPosition, 1, out _, out _).Rectangle.Left;
                     }
             }
-
-            return false;
         }
 
         /// <inheritdoc/>
@@ -585,7 +574,7 @@ namespace Avalonia.Media.TextFormatting
 
         public override IReadOnlyList<TextBounds> GetTextBounds(int firstTextSourceIndex, int textLength)
         {
-            if (_textRuns.Length == 0)
+            if (_indexedTextRuns is null || _indexedTextRuns.Count == 0)
             {
                 return Array.Empty<TextBounds>();
             }
@@ -607,303 +596,154 @@ namespace Avalonia.Media.TextFormatting
                 return currentDirection;
             }
 
-            if (_paragraphProperties.FlowDirection == FlowDirection.LeftToRight)
+            IndexedTextRun FindIndexedRun()
             {
-                var currentX = Start;
+                var i = 0;
 
-                for (int i = 0; i < _textRuns.Length; i++)
-                {
-                    var currentRun = _textRuns[i];
+                IndexedTextRun currentIndexedRun = _indexedTextRuns[i];
 
-                    var firstRunIndex = i;
-                    var lastRunIndex = firstRunIndex;
-                    var currentDirection = GetDirection(currentRun, FlowDirection.LeftToRight);
-                    var directionalWidth = 0.0;
-
-                    if (currentRun is DrawableTextRun currentDrawable)
+                while (currentIndexedRun.TextSourceCharacterIndex != currentPosition)
+                {
+                    if (i + 1 < _indexedTextRuns.Count)
                     {
-                        directionalWidth = currentDrawable.Size.Width;
-                    }
+                        i++;
 
-                    // Find consecutive runs of same direction
-                    for (; lastRunIndex + 1 < _textRuns.Length; lastRunIndex++)
-                    {
-                        var nextRun = _textRuns[lastRunIndex + 1];
+                        currentIndexedRun = _indexedTextRuns[i];
+                    }
+                }
 
-                        var nextDirection = GetDirection(nextRun, currentDirection);
+                return currentIndexedRun;
+            }
 
-                        if (currentDirection != nextDirection)
-                        {
-                            break;
-                        }
+            double GetPreceedingDistance(int firstIndex)
+            {
+                var distance = 0.0;
 
-                        if (nextRun is DrawableTextRun nextDrawable)
-                        {
-                            directionalWidth += nextDrawable.Size.Width;
-                        }
-                    }
+                for (var i = 0; i < firstIndex; i++)
+                {
+                    var currentRun = _textRuns[i];
 
-                    //Skip runs that are not part of the hit test range
-                    switch (currentDirection)
+                    if (currentRun is DrawableTextRun drawableTextRun)
                     {
-                        case FlowDirection.RightToLeft:
-                            {
-                                for (; lastRunIndex >= firstRunIndex; lastRunIndex--)
-                                {
-                                    currentRun = _textRuns[lastRunIndex];
+                        distance += drawableTextRun.Size.Width;
+                    }
+                }
 
-                                    if (currentPosition + currentRun.Length > firstTextSourceIndex)
-                                    {
-                                        break;
-                                    }
+                return distance;
+            }
 
-                                    currentPosition += currentRun.Length;
+            while (remainingLength > 0 && currentPosition < FirstTextSourceIndex + Length)
+            {
+                var currentIndexedRun = FindIndexedRun();
 
-                                    if (currentRun is DrawableTextRun drawableTextRun)
-                                    {
-                                        directionalWidth -= drawableTextRun.Size.Width;
-                                        currentX += drawableTextRun.Size.Width;
-                                    }
+                if (currentIndexedRun == null)
+                {
+                    break;
+                }
 
-                                    if (lastRunIndex - 1 < 0)
-                                    {
-                                        break;
-                                    }
-                                }
+                var directionalWidth = 0.0;
+                var firstRunIndex = currentIndexedRun.RunIndex;
+                var lastRunIndex = firstRunIndex;
+                var currentTextRun = currentIndexedRun.TextRun;
 
-                                break;
-                            }
-                        default:
-                            {
-                                for (; firstRunIndex <= lastRunIndex; firstRunIndex++)
-                                {
-                                    currentRun = _textRuns[firstRunIndex];
-
-                                    if (currentPosition + currentRun.Length > firstTextSourceIndex)
-                                    {
-                                        break;
-                                    }
+                if (currentTextRun == null)
+                {
+                    break;
+                }
 
-                                    currentPosition += currentRun.Length;
+                var currentDirection = GetDirection(currentTextRun, _resolvedFlowDirection);
 
-                                    if (currentRun is DrawableTextRun drawableTextRun)
-                                    {
-                                        currentX += drawableTextRun.Size.Width;
-                                        directionalWidth -= drawableTextRun.Size.Width;
-                                    }
+                if (currentIndexedRun.TextSourceCharacterIndex + currentTextRun.Length <= firstTextSourceIndex)
+                {
+                    currentPosition += currentTextRun.Length;
 
-                                    if (firstRunIndex + 1 == _textRuns.Length)
-                                    {
-                                        break;
-                                    }
-                                }
+                    continue;
+                }
 
-                                break;
-                            }
-                    }
+                var currentX = Start + GetPreceedingDistance(currentIndexedRun.RunIndex);
 
-                    i = lastRunIndex;
+                if (currentTextRun is DrawableTextRun currentDrawable)
+                {
+                    directionalWidth = currentDrawable.Size.Width;
+                }
 
-                    //Possible overlap at runs of different direction
-                    if (directionalWidth == 0 && i < _textRuns.Length - 1)
+                if (currentTextRun is not TextEndOfLine)
+                {
+                    if (currentDirection == FlowDirection.LeftToRight)
                     {
-                        //In case a run only contains a linebreak we don't want to skip it.
-                        if (currentRun is ShapedTextRun shaped)
-                        {
-                            if (currentRun.Length - shaped.GlyphRun.Metrics.NewLineLength > 0)
-                            {
-                                continue;
-                            }
-                        }
-                        else
+                        // Find consecutive runs of same direction
+                        for (; lastRunIndex + 1 < _textRuns.Length; lastRunIndex++)
                         {
-                            continue;
-                        }
-                    }
+                            var nextRun = _textRuns[lastRunIndex + 1];
 
-                    int coveredLength;
-                    TextBounds? textBounds;
+                            var nextDirection = GetDirection(nextRun, currentDirection);
 
-                    switch (currentDirection)
-                    {
-
-                        case FlowDirection.RightToLeft:
+                            if (currentDirection != nextDirection)
                             {
-                                textBounds = GetTextRunBoundsRightToLeft(firstRunIndex, lastRunIndex, currentX + directionalWidth, firstTextSourceIndex,
-                                        currentPosition, remainingLength, out coveredLength, out currentPosition);
-
-                                currentX += directionalWidth;
-
                                 break;
                             }
-                        default:
-                            {
-                                textBounds = GetTextBoundsLeftToRight(firstRunIndex, lastRunIndex, currentX, firstTextSourceIndex,
-                                        currentPosition, remainingLength, out coveredLength, out currentPosition);
 
-                                currentX = textBounds.Rectangle.Right;
-
-                                break;
+                            if (nextRun is DrawableTextRun nextDrawable)
+                            {
+                                directionalWidth += nextDrawable.Size.Width;
                             }
+                        }
                     }
-
-                    if (coveredLength > 0)
-                    {
-                        result.Add(textBounds);
-
-                        remainingLength -= coveredLength;
-                    }
-
-                    if (remainingLength <= 0)
-                    {
-                        break;
-                    }
-                }
-            }
-            else
-            {
-                var currentX = Start + WidthIncludingTrailingWhitespace;
-
-                for (int i = _textRuns.Length - 1; i >= 0; i--)
-                {
-                    var currentRun = _textRuns[i];
-                    var firstRunIndex = i;
-                    var lastRunIndex = firstRunIndex;
-                    var currentDirection = GetDirection(currentRun, FlowDirection.RightToLeft);
-                    var directionalWidth = 0.0;
-
-                    if (currentRun is DrawableTextRun currentDrawable)
-                    {
-                        directionalWidth = currentDrawable.Size.Width;
-                    }
-
-                    // Find consecutive runs of same direction
-                    for (; firstRunIndex - 1 > 0; firstRunIndex--)
+                    else
                     {
-                        var previousRun = _textRuns[firstRunIndex - 1];
-
-                        var previousDirection = GetDirection(previousRun, currentDirection);
-
-                        if (currentDirection != previousDirection)
+                        // Find consecutive runs of same direction
+                        for (; firstRunIndex - 1 > 0; firstRunIndex--)
                         {
-                            break;
-                        }
+                            var previousRun = _textRuns[firstRunIndex - 1];
 
-                        if (currentRun is DrawableTextRun previousDrawable)
-                        {
-                            directionalWidth += previousDrawable.Size.Width;
-                        }
-                    }
+                            var previousDirection = GetDirection(previousRun, currentDirection);
 
-                    //Skip runs that are not part of the hit test range
-                    switch (currentDirection)
-                    {
-                        case FlowDirection.RightToLeft:
+                            if (currentDirection != previousDirection)
                             {
-                                for (; lastRunIndex >= firstRunIndex; lastRunIndex--)
-                                {
-                                    currentRun = _textRuns[lastRunIndex];
-
-                                    if (currentPosition + currentRun.Length <= firstTextSourceIndex)
-                                    {
-                                        currentPosition += currentRun.Length;
-
-                                        if (currentRun is DrawableTextRun drawableTextRun)
-                                        {
-                                            currentX -= drawableTextRun.Size.Width;
-                                            directionalWidth -= drawableTextRun.Size.Width;
-                                        }
-
-                                        continue;
-                                    }
-
-                                    break;
-                                }
-
                                 break;
                             }
-                        default:
-                            {
-                                for (; firstRunIndex <= lastRunIndex; firstRunIndex++)
-                                {
-                                    currentRun = _textRuns[firstRunIndex];
-
-                                    if (currentPosition + currentRun.Length <= firstTextSourceIndex)
-                                    {
-                                        currentPosition += currentRun.Length;
-
-                                        if (currentRun is DrawableTextRun drawableTextRun)
-                                        {
-                                            currentX += drawableTextRun.Size.Width;
-                                            directionalWidth -= drawableTextRun.Size.Width;
-                                        }
 
-                                        continue;
-                                    }
-
-                                    break;
-                                }
+                            if (previousRun is DrawableTextRun previousDrawable)
+                            {
+                                directionalWidth += previousDrawable.Size.Width;
 
-                                break;
+                                currentX -= previousDrawable.Size.Width;
                             }
+                        }
                     }
+                }
 
-                    i = firstRunIndex;
+                int coveredLength;
+                TextBounds? textBounds;
 
-                    //Possible overlap at runs of different direction
-                    if (directionalWidth == 0 && i > 0)
-                    {
-                        //In case a run only contains a linebreak we don't want to skip it.
-                        if (currentRun is ShapedTextRun shaped)
+                switch (currentDirection)
+                {
+                    case FlowDirection.RightToLeft:
                         {
-                            if (currentRun.Length - shaped.GlyphRun.Metrics.NewLineLength > 0)
-                            {
-                                continue;
-                            }
+                            textBounds = GetTextRunBoundsRightToLeft(firstRunIndex, lastRunIndex, currentX + directionalWidth, firstTextSourceIndex,
+                                    currentPosition, remainingLength, out coveredLength, out currentPosition);
+
+                            break;
                         }
-                        else
+                    default:
                         {
-                            continue;
-                        }
-                    }
-
-                    int coveredLength;
-                    TextBounds? textBounds;
-
-                    switch (currentDirection)
-                    {
-                        case FlowDirection.LeftToRight:
-                            {
-                                textBounds = GetTextBoundsLeftToRight(firstRunIndex, lastRunIndex, currentX - directionalWidth, firstTextSourceIndex,
-                                        currentPosition, remainingLength, out coveredLength, out currentPosition);
-
-                                currentX -= directionalWidth;
-
-                                break;
-                            }
-                        default:
-                            {
-                                textBounds = GetTextRunBoundsRightToLeft(firstRunIndex, lastRunIndex, currentX, firstTextSourceIndex,
-                                        currentPosition, remainingLength, out coveredLength, out currentPosition);
-
-                                currentX = textBounds.Rectangle.Left;
+                            textBounds = GetTextBoundsLeftToRight(firstRunIndex, lastRunIndex, currentX, firstTextSourceIndex,
+                                    currentPosition, remainingLength, out coveredLength, out currentPosition);
 
-                                break;
-                            }
-                    }
+                            break;
+                        }
+                }
 
-                    //Visual order is always left to right so we need to insert
-                    result.Insert(0, textBounds);
+                if (coveredLength > 0)
+                {
+                    result.Add(textBounds);
 
                     remainingLength -= coveredLength;
-
-                    if (remainingLength <= 0)
-                    {
-                        break;
-                    }
                 }
             }
 
+            result.Sort(TextBoundsComparer);
+
             return result;
         }
 
@@ -1164,7 +1004,7 @@ namespace Avalonia.Media.TextFormatting
                 _textLineBreak = new TextLineBreak(textEndOfLine);
             }
 
-            BidiReorderer.Instance.BidiReorder(_textRuns, _resolvedFlowDirection);
+            _indexedTextRuns = BidiReorderer.Instance.BidiReorder(_textRuns, _paragraphProperties.FlowDirection, FirstTextSourceIndex);
         }
 
         /// <summary>
@@ -1211,13 +1051,6 @@ namespace Avalonia.Media.TextFormatting
                                 return true;
                             }
 
-                            //var characterIndex = codepointIndex - shapedRun.Text.Start;
-
-                            //if (characterIndex < 0 && shapedRun.ShapedBuffer.IsLeftToRight)
-                            //{
-                            //    foundCharacterHit = new CharacterHit(foundCharacterHit.FirstCharacterIndex);
-                            //}
-
                             nextCharacterHit = isAtEnd || characterHit.TrailingLength != 0 ?
                                 foundCharacterHit :
                                 new CharacterHit(foundCharacterHit.FirstCharacterIndex + foundCharacterHit.TrailingLength);
@@ -1556,8 +1389,8 @@ namespace Avalonia.Media.TextFormatting
                 TrailingWhitespaceLength = trailingWhitespaceLength,
                 Width = width,
                 WidthIncludingTrailingWhitespace = widthIncludingWhitespace,
-                OverhangLeading= overhangLeading,
-                OverhangTrailing= overhangTrailing,
+                OverhangLeading = overhangLeading,
+                OverhangTrailing = overhangTrailing,
                 OverhangAfter = overhangAfter
             };
         }
@@ -1615,8 +1448,7 @@ namespace Avalonia.Media.TextFormatting
 
                     return Math.Max(0, start);
                 case TextAlignment.Right:
-                    return Math.Max(0, _paragraphWidth - width);
-
+                    return Math.Max(0, _paragraphWidth - widthIncludingTrailingWhitespace);
                 default:
                     return 0;
             }
diff --git a/src/Avalonia.Base/Media/TileBrush.cs b/src/Avalonia.Base/Media/TileBrush.cs
index 47a617a4fb..b248d30410 100644
--- a/src/Avalonia.Base/Media/TileBrush.cs
+++ b/src/Avalonia.Base/Media/TileBrush.cs
@@ -41,6 +41,11 @@ namespace Avalonia.Media
     /// </summary>
     public abstract class TileBrush : Brush, ITileBrush
     {
+        internal TileBrush()
+        {
+            
+        }
+        
         /// <summary>
         /// Defines the <see cref="AlignmentX"/> property.
         /// </summary>
diff --git a/src/Avalonia.Base/Media/Transform.cs b/src/Avalonia.Base/Media/Transform.cs
index 2934291626..1ac81808a1 100644
--- a/src/Avalonia.Base/Media/Transform.cs
+++ b/src/Avalonia.Base/Media/Transform.cs
@@ -21,6 +21,11 @@ namespace Avalonia.Media
                 typeof(ITransform).IsAssignableFrom(prop.OwnerType));
         }
 
+        internal Transform()
+        {
+            
+        }
+
         /// <summary>
         /// Raised when the transform changes.
         /// </summary>
diff --git a/src/Avalonia.Base/Media/TransformGroup.cs b/src/Avalonia.Base/Media/TransformGroup.cs
index ae5e54c414..38069f783a 100644
--- a/src/Avalonia.Base/Media/TransformGroup.cs
+++ b/src/Avalonia.Base/Media/TransformGroup.cs
@@ -3,7 +3,7 @@ using Avalonia.Metadata;
 
 namespace Avalonia.Media
 {
-    public class TransformGroup : Transform
+    public sealed class TransformGroup : Transform
     {
         /// <summary>
         /// Defines the <see cref="Children"/> property.
diff --git a/src/Avalonia.Base/Media/TranslateTransform.cs b/src/Avalonia.Base/Media/TranslateTransform.cs
index 1d0169a62c..34cebe9150 100644
--- a/src/Avalonia.Base/Media/TranslateTransform.cs
+++ b/src/Avalonia.Base/Media/TranslateTransform.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Media
     /// <summary>
     /// Translates (moves) an <see cref="Visual"/>.
     /// </summary>
-    public class TranslateTransform : Transform
+    public sealed class TranslateTransform : Transform
     {
         /// <summary>
         /// Defines the <see cref="X"/> property.
diff --git a/src/Avalonia.Base/Media/VisualBrush.cs b/src/Avalonia.Base/Media/VisualBrush.cs
index a1be9a9202..15d4f39d6c 100644
--- a/src/Avalonia.Base/Media/VisualBrush.cs
+++ b/src/Avalonia.Base/Media/VisualBrush.cs
@@ -12,7 +12,7 @@ namespace Avalonia.Media
     /// <summary>
     /// Paints an area with an <see cref="Visual"/>.
     /// </summary>
-    public class VisualBrush : TileBrush, ISceneBrush
+    public sealed class VisualBrush : TileBrush, ISceneBrush
     {
         /// <summary>
         /// Defines the <see cref="Visual"/> property.
@@ -64,7 +64,7 @@ namespace Avalonia.Media
 
         private InlineDictionary<Compositor, CompositionRenderDataSceneBrushContent?> _renderDataDictionary;
 
-        protected override void OnReferencedFromCompositor(Compositor c)
+        private protected override void OnReferencedFromCompositor(Compositor c)
         {
             _renderDataDictionary.Add(c, CreateServerContent(c));
             base.OnReferencedFromCompositor(c);
diff --git a/src/Avalonia.Base/Metadata/PrivateApiAttribute.cs b/src/Avalonia.Base/Metadata/PrivateApiAttribute.cs
index 8848a6b629..8246d4a18d 100644
--- a/src/Avalonia.Base/Metadata/PrivateApiAttribute.cs
+++ b/src/Avalonia.Base/Metadata/PrivateApiAttribute.cs
@@ -2,7 +2,8 @@ using System;
 
 namespace Avalonia.Metadata;
 
-[AttributeUsage(AttributeTargets.Interface | AttributeTargets.Class | AttributeTargets.Constructor | AttributeTargets.Method)]
+[AttributeUsage(AttributeTargets.Interface | AttributeTargets.Class | AttributeTargets.Constructor 
+                | AttributeTargets.Method | AttributeTargets.Property | AttributeTargets.Field | AttributeTargets.Struct)]
 public sealed class PrivateApiAttribute : Attribute
 {
 
diff --git a/src/Avalonia.Base/Platform/IDrawingContextImpl.cs b/src/Avalonia.Base/Platform/IDrawingContextImpl.cs
index 8416354bc2..a0cd2a8dcd 100644
--- a/src/Avalonia.Base/Platform/IDrawingContextImpl.cs
+++ b/src/Avalonia.Base/Platform/IDrawingContextImpl.cs
@@ -132,7 +132,7 @@ namespace Avalonia.Platform
         /// </summary>
         /// <param name="opacity">The opacity.</param>
         /// <param name="bounds">where to apply the opacity.</param>
-        void PushOpacity(double opacity, Rect bounds);
+        void PushOpacity(double opacity, Rect? bounds);
 
         /// <summary>
         /// Pops the latest pushed opacity value.
diff --git a/src/Avalonia.Base/Platform/IModuleEnvironmentChecker.cs b/src/Avalonia.Base/Platform/IModuleEnvironmentChecker.cs
deleted file mode 100644
index d8d3a19af6..0000000000
--- a/src/Avalonia.Base/Platform/IModuleEnvironmentChecker.cs
+++ /dev/null
@@ -1,7 +0,0 @@
-namespace Avalonia.Platform
-{
-    public interface IModuleEnvironmentChecker
-    {
-        bool IsCompatible { get; }
-    }
-}
\ No newline at end of file
diff --git a/src/Avalonia.Base/Platform/IPlatformThreadingInterface.cs b/src/Avalonia.Base/Platform/IPlatformThreadingInterface.cs
index 4fe4a2e6b9..71b339ec50 100644
--- a/src/Avalonia.Base/Platform/IPlatformThreadingInterface.cs
+++ b/src/Avalonia.Base/Platform/IPlatformThreadingInterface.cs
@@ -8,7 +8,7 @@ namespace Avalonia.Platform
     /// <summary>
     /// Provides platform-specific services relating to threading.
     /// </summary>
-    [Unstable]
+    [PrivateApi]
     public interface IPlatformThreadingInterface
     {
         /// <summary>
diff --git a/src/Avalonia.Base/Platform/IRenderTarget.cs b/src/Avalonia.Base/Platform/IRenderTarget.cs
index 31ad84341d..2b4584483e 100644
--- a/src/Avalonia.Base/Platform/IRenderTarget.cs
+++ b/src/Avalonia.Base/Platform/IRenderTarget.cs
@@ -1,4 +1,5 @@
 using System;
+using Avalonia.Metadata;
 using Avalonia.Rendering;
 
 namespace Avalonia.Platform
@@ -9,6 +10,7 @@ namespace Avalonia.Platform
     /// <remarks>
     /// The interface used for obtaining drawing context from surfaces you can render on.
     /// </remarks>
+    [PrivateApi]
     public interface IRenderTarget : IDisposable
     {
         /// <summary>
diff --git a/src/Avalonia.Base/Platform/Interop/IDynamicLibraryLoader.cs b/src/Avalonia.Base/Platform/Interop/IDynamicLibraryLoader.cs
index d9db4b71d5..56c50e340d 100644
--- a/src/Avalonia.Base/Platform/Interop/IDynamicLibraryLoader.cs
+++ b/src/Avalonia.Base/Platform/Interop/IDynamicLibraryLoader.cs
@@ -3,7 +3,6 @@ using Avalonia.Metadata;
 
 namespace Avalonia.Platform.Interop
 {
-    [Unstable]
     public interface IDynamicLibraryLoader
     {
         IntPtr LoadLibrary(string dll);
diff --git a/src/Avalonia.Base/Platform/Interop/Utf8Buffer.cs b/src/Avalonia.Base/Platform/Interop/Utf8Buffer.cs
index 7a0b5b34cd..8fef283b58 100644
--- a/src/Avalonia.Base/Platform/Interop/Utf8Buffer.cs
+++ b/src/Avalonia.Base/Platform/Interop/Utf8Buffer.cs
@@ -5,7 +5,7 @@ using System.Text;
 
 namespace Avalonia.Platform.Interop
 {
-    public class Utf8Buffer : SafeHandle
+    internal class Utf8Buffer : SafeHandle
     {
         private GCHandle _gcHandle;
         private byte[]? _data;
diff --git a/src/Avalonia.Base/PropertyStore/EffectiveValue`1.cs b/src/Avalonia.Base/PropertyStore/EffectiveValue`1.cs
index b725326855..4518289335 100644
--- a/src/Avalonia.Base/PropertyStore/EffectiveValue`1.cs
+++ b/src/Avalonia.Base/PropertyStore/EffectiveValue`1.cs
@@ -208,7 +208,7 @@ namespace Avalonia.PropertyStore
             IsOverridenCurrentValue = isOverriddenCurrentValue;
             IsCoercedDefaultValue = isCoercedDefaultValue;
 
-            if (_uncommon?._coerce is { } coerce)
+            if (!isCoercedDefaultValue && _uncommon?._coerce is { } coerce)
                 v = coerce(owner.Owner, value);
 
             if (priority <= Priority)
@@ -262,7 +262,8 @@ namespace Avalonia.PropertyStore
             if (_uncommon?._coerce is { } coerce)
             {
                 v = coerce(owner.Owner, value);
-                bv = coerce(owner.Owner, baseValue);
+                if (priority != basePriority)
+                    bv = coerce(owner.Owner, baseValue);
             }
 
             if (!EqualityComparer<T>.Default.Equals(Value, v))
diff --git a/src/Avalonia.Base/Reactive/SingleSubscriberObservableBase.cs b/src/Avalonia.Base/Reactive/SingleSubscriberObservableBase.cs
index 53a0b43c63..10d42214c2 100644
--- a/src/Avalonia.Base/Reactive/SingleSubscriberObservableBase.cs
+++ b/src/Avalonia.Base/Reactive/SingleSubscriberObservableBase.cs
@@ -3,7 +3,7 @@ using Avalonia.Threading;
 
 namespace Avalonia.Reactive
 {
-    public abstract class SingleSubscriberObservableBase<T> : IObservable<T>, IDisposable
+    internal abstract class SingleSubscriberObservableBase<T> : IObservable<T>, IDisposable
     {
         private Exception? _error;
         private IObserver<T>? _observer;
diff --git a/src/Avalonia.Base/Rendering/Composition/CompositingRenderer.cs b/src/Avalonia.Base/Rendering/Composition/CompositingRenderer.cs
index b6fe265531..61a3f7e831 100644
--- a/src/Avalonia.Base/Rendering/Composition/CompositingRenderer.cs
+++ b/src/Avalonia.Base/Rendering/Composition/CompositingRenderer.cs
@@ -17,7 +17,7 @@ namespace Avalonia.Rendering.Composition;
 /// <summary>
 /// A renderer that utilizes <see cref="Avalonia.Rendering.Composition.Compositor"/> to render the visual tree 
 /// </summary>
-public class CompositingRenderer : IRendererWithCompositor
+internal class CompositingRenderer : IRendererWithCompositor, IHitTester
 {
     private readonly IRenderRoot _root;
     private readonly Compositor _compositor;
@@ -32,11 +32,6 @@ public class CompositingRenderer : IRendererWithCompositor
 
     internal CompositionTarget CompositionTarget { get; }
     
-    /// <summary>
-    /// Asks the renderer to only draw frames on the render thread. Makes Paint to wait until frame is rendered.
-    /// </summary>
-    public bool RenderOnlyOnRenderThread { get; set; } = true;
-
     /// <inheritdoc/>
     public RendererDiagnostics Diagnostics { get; }
 
@@ -303,6 +298,9 @@ public class CompositingRenderer : IRendererWithCompositor
         await batchCompletion;
         SceneInvalidated?.Invoke(this, new SceneInvalidatedEventArgs(_root, new Rect(_root.ClientSize)));
     }
+
+    public void TriggerSceneInvalidatedForUnitTests(Rect rect) =>
+        SceneInvalidated?.Invoke(this, new SceneInvalidatedEventArgs(_root, rect));
     
     private void Update()
     {
@@ -332,10 +330,7 @@ public class CompositingRenderer : IRendererWithCompositor
 
         QueueUpdate();
         CompositionTarget.RequestRedraw();
-        if(RenderOnlyOnRenderThread && Compositor.Loop.RunsInBackground)
-            Compositor.Commit().Wait();
-        else
-            CompositionTarget.ImmediateUIThreadRender();
+        MediaContext.Instance.ImmediateRenderRequested(CompositionTarget);
     }
 
     /// <inheritdoc />
@@ -355,6 +350,8 @@ public class CompositingRenderer : IRendererWithCompositor
     public ValueTask<object?> TryGetRenderInterfaceFeature(Type featureType)
         => Compositor.TryGetRenderInterfaceFeature(featureType);
 
+    public bool IsDisposed => _isDisposed;
+    
     /// <inheritdoc />
     public void Dispose()
     {
@@ -367,11 +364,7 @@ public class CompositingRenderer : IRendererWithCompositor
         SceneInvalidated = null;
 
         Stop();
-        CompositionTarget.Dispose();
-        
-        // Wait for the composition batch to be applied and rendered to guarantee that
-        // render target is not used anymore and can be safely disposed
-        if (Compositor.Loop.RunsInBackground)
-            _compositor.Commit().Wait();
+
+        MediaContext.Instance.SyncDisposeCompositionTarget(CompositionTarget);
     }
 }
diff --git a/src/Avalonia.Base/Rendering/Composition/CompositionTarget.cs b/src/Avalonia.Base/Rendering/Composition/CompositionTarget.cs
index 492ea774bc..91d2fb59de 100644
--- a/src/Avalonia.Base/Rendering/Composition/CompositionTarget.cs
+++ b/src/Avalonia.Base/Rendering/Composition/CompositionTarget.cs
@@ -122,14 +122,5 @@ namespace Avalonia.Rendering.Composition
         /// Registers the composition target for explicit redraw
         /// </summary>
         public void RequestRedraw() => RegisterForSerialization();
-
-        /// <summary>
-        /// Performs composition directly on the UI thread 
-        /// </summary>
-        internal void ImmediateUIThreadRender()
-        {
-            Compositor.Commit();
-            Compositor.Server.Render();
-        }
     }
 }
diff --git a/src/Avalonia.Base/Rendering/Composition/Compositor.cs b/src/Avalonia.Base/Rendering/Composition/Compositor.cs
index a2398fdb61..dde9dcd6fb 100644
--- a/src/Avalonia.Base/Rendering/Composition/Compositor.cs
+++ b/src/Avalonia.Base/Rendering/Composition/Compositor.cs
@@ -25,25 +25,39 @@ namespace Avalonia.Rendering.Composition
     public partial class Compositor
     {
         internal IRenderLoop Loop { get; }
+        internal bool UseUiThreadForSynchronousCommits { get; }
         private ServerCompositor _server;
-        private TaskCompletionSource<int>? _nextCommit;
-        private Action _commit;
-        private BatchStreamObjectPool<object?> _batchObjectPool = new();
-        private BatchStreamMemoryPool _batchMemoryPool = new();
+        private Batch? _nextCommit;
+        private BatchStreamObjectPool<object?> _batchObjectPool;
+        private BatchStreamMemoryPool _batchMemoryPool;
         private Queue<ICompositorSerializable> _objectSerializationQueue = new();
         private HashSet<ICompositorSerializable> _objectSerializationHashSet = new();
         private Queue<Action> _invokeBeforeCommitWrite = new(), _invokeBeforeCommitRead = new();
         private HashSet<IDisposable> _disposeOnNextBatch = new();
         internal ServerCompositor Server => _server;
-        private Task? _pendingBatch;
+        private Batch? _pendingBatch;
         private readonly object _pendingBatchLock = new();
         private List<Action> _pendingServerCompositorJobs = new();
         private DiagnosticTextRenderer? _diagnosticTextRenderer;
+        private Action _triggerCommitRequested;
 
         internal IEasing DefaultEasing { get; }
 
-        private DiagnosticTextRenderer DiagnosticTextRenderer
-            => _diagnosticTextRenderer ??= new(Typeface.Default.GlyphTypeface, 12.0);
+        private DiagnosticTextRenderer? DiagnosticTextRenderer
+        {
+            get
+            {
+                if (_diagnosticTextRenderer == null)
+                {
+                    // We are running in some unit test context
+                    if (AvaloniaLocator.Current.GetService<IFontManagerImpl>() == null)
+                        return null;
+                    _diagnosticTextRenderer = new(Typeface.Default.GlyphTypeface, 12.0);
+                }
+
+                return _diagnosticTextRenderer;
+            }
+        }
 
         internal event Action? AfterCommit;
 
@@ -51,14 +65,27 @@ namespace Avalonia.Rendering.Composition
         /// <summary>
         /// Creates a new compositor on a specified render loop that would use a particular GPU
         /// </summary>
-        /// <param name="loop"></param>
-        /// <param name="gpu"></param>
         [PrivateApi]
-        public Compositor(IRenderLoop loop, IPlatformGraphics? gpu)
+        public Compositor(IPlatformGraphics? gpu, bool useUiThreadForSynchronousCommits = false)
+            : this(RenderLoop.LocatorAutoInstance, gpu, useUiThreadForSynchronousCommits)
+        {
+        }
+
+        internal Compositor(IRenderLoop loop, IPlatformGraphics? gpu, bool useUiThreadForSynchronousCommits = false)
+            : this(loop, gpu, useUiThreadForSynchronousCommits, MediaContext.Instance, false)
+        {
+        }
+
+        internal Compositor(IRenderLoop loop, IPlatformGraphics? gpu,
+            bool useUiThreadForSynchronousCommits,
+            ICompositorScheduler scheduler, bool reclaimBuffersImmediately)
         {
             Loop = loop;
+            UseUiThreadForSynchronousCommits = useUiThreadForSynchronousCommits;
+            _batchMemoryPool = new(reclaimBuffersImmediately);
+            _batchObjectPool = new(reclaimBuffersImmediately);
             _server = new ServerCompositor(loop, gpu, _batchObjectPool, _batchMemoryPool);
-            _commit = () => Commit();
+            _triggerCommitRequested = () => scheduler.CommitRequested(this);
 
             DefaultEasing = new CubicBezierEasing(new Point(0.25f, 0.1f), new Point(0.25f, 1f));
         }
@@ -72,23 +99,19 @@ namespace Avalonia.Rendering.Composition
             Dispatcher.UIThread.VerifyAccess();
             if (_nextCommit == null)
             {
-                _nextCommit = new TaskCompletionSource<int>();
+                _nextCommit = new ();
                 var pending = _pendingBatch;
                 if (pending != null)
-                {
-                    pending.ContinueWith(_ =>
-                    {
-                        Dispatcher.UIThread.Post(_commit, DispatcherPriority.Composition);
-                    });
-                }
+                    pending.Processed.ContinueWith(
+                        _ => Dispatcher.UIThread.Post(_triggerCommitRequested, DispatcherPriority.Send));
                 else
-                    Dispatcher.UIThread.Post(_commit, DispatcherPriority.Composition);
+                    _triggerCommitRequested();
             }
 
-            return _nextCommit.Task;
+            return _nextCommit.Processed;
         }
 
-        internal Task Commit()
+        internal Batch Commit()
         {
             try
             {
@@ -102,20 +125,18 @@ namespace Avalonia.Rendering.Composition
             }
         }
         
-        Task CommitCore()
+        Batch CommitCore()
         {
             Dispatcher.UIThread.VerifyAccess();
             using var noPump = NonPumpingLockHelper.Use();
             
-            _nextCommit ??= new TaskCompletionSource<int>();
+            _nextCommit ??= new();
 
             (_invokeBeforeCommitRead, _invokeBeforeCommitWrite) = (_invokeBeforeCommitWrite, _invokeBeforeCommitRead);
             while (_invokeBeforeCommitRead.Count > 0)
                 _invokeBeforeCommitRead.Dequeue()();
             
-            var batch = new Batch(_nextCommit);
-            
-            using (var writer = new BatchStreamWriter(batch.Changes, _batchMemoryPool, _batchObjectPool))
+            using (var writer = new BatchStreamWriter(_nextCommit.Changes, _batchMemoryPool, _batchObjectPool))
             {
                 while(_objectSerializationQueue.TryDequeue(out var obj))
                 {
@@ -151,17 +172,17 @@ namespace Avalonia.Rendering.Composition
                 _pendingServerCompositorJobs.Clear();
             }
             
-            batch.CommittedAt = Server.Clock.Elapsed;
-            _server.EnqueueBatch(batch);
+            _nextCommit.CommittedAt = Server.Clock.Elapsed;
+            _server.EnqueueBatch(_nextCommit);
             
             lock (_pendingBatchLock)
             {
-                _pendingBatch = _nextCommit.Task;
-                _pendingBatch.ContinueWith(t =>
+                _pendingBatch = _nextCommit;
+                _pendingBatch.Processed.ContinueWith(t =>
                 {
                     lock (_pendingBatchLock)
                     {
-                        if (_pendingBatch == t)
+                        if (_pendingBatch.Processed == t)
                             _pendingBatch = null;
                     }
                 }, TaskContinuationOptions.ExecuteSynchronously);
@@ -257,4 +278,9 @@ namespace Avalonia.Rendering.Composition
         internal bool UnitTestIsRegisteredForSerialization(ICompositorSerializable serializable) =>
             _objectSerializationHashSet.Contains(serializable);
     }
+    
+    internal interface ICompositorScheduler
+    {
+        void CommitRequested(Compositor compositor);
+    }
 }
diff --git a/src/Avalonia.Base/Rendering/Composition/Drawing/Nodes/RenderDataNodes.cs b/src/Avalonia.Base/Rendering/Composition/Drawing/Nodes/RenderDataNodes.cs
index 3012432e12..2d3b5b0f22 100644
--- a/src/Avalonia.Base/Rendering/Composition/Drawing/Nodes/RenderDataNodes.cs
+++ b/src/Avalonia.Base/Rendering/Composition/Drawing/Nodes/RenderDataNodes.cs
@@ -182,11 +182,10 @@ class RenderDataGeometryClipNode : RenderDataPushNode
 class RenderDataOpacityNode : RenderDataPushNode
 {
     public double Opacity { get; set; }
-    public Rect BoundsRect { get; set; }
     public override void Push(ref RenderDataNodeRenderContext context)
     {
         if (Opacity != 1)
-            context.Context.PushOpacity(Opacity, BoundsRect);
+            context.Context.PushOpacity(Opacity, null);
     }
 
     public override void Pop(ref RenderDataNodeRenderContext context)
@@ -211,4 +210,4 @@ abstract class RenderDataBrushAndPenNode : IRenderDataItemWithServerResources
     public abstract void Invoke(ref RenderDataNodeRenderContext context);
     public abstract Rect? Bounds { get; }
     public abstract bool HitTest(Point p);
-}
\ No newline at end of file
+}
diff --git a/src/Avalonia.Base/Rendering/Composition/Drawing/RenderDataDrawingContext.cs b/src/Avalonia.Base/Rendering/Composition/Drawing/RenderDataDrawingContext.cs
index 3d5033086e..e7b14f138d 100644
--- a/src/Avalonia.Base/Rendering/Composition/Drawing/RenderDataDrawingContext.cs
+++ b/src/Avalonia.Base/Rendering/Composition/Drawing/RenderDataDrawingContext.cs
@@ -79,12 +79,19 @@ internal class RenderDataDrawingContext : DrawingContext
 
         if (!(parent.Node is T))
             throw new InvalidOperationException("Invalid Pop operation");
-        
-        foreach(var item in _currentItemList!)
-            parent.Node.Children.Add(item);
-        _currentItemList.Clear();
-        s_listPool.ReturnAndSetNull(ref _currentItemList);
+
+        var removeLastPush = true;
+        if (_currentItemList != null)
+        {
+            removeLastPush = _currentItemList.Count == 0;
+            foreach (var item in _currentItemList)
+                parent.Node.Children.Add(item);
+            _currentItemList.Clear();
+            s_listPool.ReturnAndSetNull(ref _currentItemList);
+        }
         _currentItemList = parent.Items;
+        if (removeLastPush)
+            _currentItemList.RemoveAt(_currentItemList.Count - 1);
     }
 
     void AddResource(object? resource)
@@ -177,7 +184,10 @@ internal class RenderDataDrawingContext : DrawingContext
         });
     }
 
-    public override void Custom(ICustomDrawOperation custom) => Add(new RenderDataCustomNode());
+    public override void Custom(ICustomDrawOperation custom) => Add(new RenderDataCustomNode
+    {
+        Operation = custom
+    });
 
     public override void DrawGlyphRun(IBrush? foreground, GlyphRun? glyphRun)
     {
@@ -212,15 +222,14 @@ internal class RenderDataDrawingContext : DrawingContext
             });
     }
 
-    protected override void PushOpacityCore(double opacity, Rect bounds)
+    protected override void PushOpacityCore(double opacity)
     {
         if (opacity == 1)
             Push();
         else
             Push(new RenderDataOpacityNode
             {
-                Opacity = opacity,
-                BoundsRect = bounds
+                Opacity = opacity
             });
     }
 
@@ -346,4 +355,4 @@ internal class RenderDataDrawingContext : DrawingContext
         if (_resourcesHashSet != null) 
             s_hashSetPool.ReturnAndSetNull(ref _resourcesHashSet);
     }
-}
\ No newline at end of file
+}
diff --git a/src/Avalonia.Base/Rendering/Composition/Drawing/ServerResourceHelperExtensions.cs b/src/Avalonia.Base/Rendering/Composition/Drawing/ServerResourceHelperExtensions.cs
index 63b81a742c..2a6971e8ea 100644
--- a/src/Avalonia.Base/Rendering/Composition/Drawing/ServerResourceHelperExtensions.cs
+++ b/src/Avalonia.Base/Rendering/Composition/Drawing/ServerResourceHelperExtensions.cs
@@ -50,7 +50,6 @@ static class ServerResourceHelperExtensions
             return immutable;
         if (transform is ICompositionRenderResource<ITransform> resource)
             resource.GetForCompositor(compositor);
-        ThrowNotCompatible(transform);
-        return null;
+        return new ImmutableTransform(transform.Value);
     }
 }
\ No newline at end of file
diff --git a/src/Avalonia.Base/Rendering/Composition/Server/DrawingContextProxy.cs b/src/Avalonia.Base/Rendering/Composition/Server/DrawingContextProxy.cs
index b735b106d8..14dd59b7e3 100644
--- a/src/Avalonia.Base/Rendering/Composition/Server/DrawingContextProxy.cs
+++ b/src/Avalonia.Base/Rendering/Composition/Server/DrawingContextProxy.cs
@@ -109,7 +109,7 @@ internal class CompositorDrawingContextProxy : IDrawingContextImpl,
         _impl.PopClip();
     }
 
-    public void PushOpacity(double opacity, Rect bounds)
+    public void PushOpacity(double opacity, Rect? bounds)
     {
         _impl.PushOpacity(opacity, bounds);
     }
diff --git a/src/Avalonia.Base/Rendering/Composition/Server/ServerCompositionTarget.cs b/src/Avalonia.Base/Rendering/Composition/Server/ServerCompositionTarget.cs
index 4f6564ebcf..7672bcb14d 100644
--- a/src/Avalonia.Base/Rendering/Composition/Server/ServerCompositionTarget.cs
+++ b/src/Avalonia.Base/Rendering/Composition/Server/ServerCompositionTarget.cs
@@ -21,7 +21,7 @@ namespace Avalonia.Rendering.Composition.Server
     {
         private readonly ServerCompositor _compositor;
         private readonly Func<IEnumerable<object>> _surfaces;
-        private readonly DiagnosticTextRenderer _diagnosticTextRenderer;
+        private readonly DiagnosticTextRenderer? _diagnosticTextRenderer;
         private static long s_nextId = 1;
         private IRenderTarget? _renderTarget;
         private FpsCounter? _fpsCounter;
@@ -42,17 +42,17 @@ namespace Avalonia.Rendering.Composition.Server
         public ReadbackIndices Readback { get; } = new();
         public int RenderedVisuals { get; set; }
 
-        private FpsCounter FpsCounter
-            => _fpsCounter ??= new FpsCounter(_diagnosticTextRenderer);
+        private FpsCounter? FpsCounter
+            => _fpsCounter ??= _diagnosticTextRenderer != null ? new FpsCounter(_diagnosticTextRenderer) : null;
 
-        private FrameTimeGraph LayoutTimeGraph
+        private FrameTimeGraph? LayoutTimeGraph
             => _layoutTimeGraph ??= CreateTimeGraph("Layout");
 
-        private FrameTimeGraph RenderTimeGraph
+        private FrameTimeGraph? RenderTimeGraph
             => _renderTimeGraph ??= CreateTimeGraph("Render");
 
         public ServerCompositionTarget(ServerCompositor compositor, Func<IEnumerable<object>> surfaces,
-            DiagnosticTextRenderer diagnosticTextRenderer)
+            DiagnosticTextRenderer? diagnosticTextRenderer)
             : base(compositor)
         {
             _compositor = compositor;
@@ -61,8 +61,12 @@ namespace Avalonia.Rendering.Composition.Server
             Id = Interlocked.Increment(ref s_nextId);
         }
 
-        private FrameTimeGraph CreateTimeGraph(string title)
-            => new(360, new Size(360.0, 64.0), 1000.0 / 60.0, title, _diagnosticTextRenderer);
+        private FrameTimeGraph? CreateTimeGraph(string title)
+        {
+            if (_diagnosticTextRenderer == null)
+                return null;
+            return new FrameTimeGraph(360, new Size(360.0, 64.0), 1000.0 / 60.0, title, _diagnosticTextRenderer);
+        }
 
         partial void OnIsEnabledChanged()
         {
@@ -102,7 +106,7 @@ namespace Avalonia.Rendering.Composition.Server
         {
             if ((DebugOverlays & RendererDebugOverlays.LayoutTimeGraph) != 0)
             {
-                LayoutTimeGraph.AddFrameValue(LastLayoutPassTiming.Elapsed.TotalMilliseconds);
+                LayoutTimeGraph?.AddFrameValue(LastLayoutPassTiming.Elapsed.TotalMilliseconds);
             }
         }
 
@@ -188,7 +192,7 @@ namespace Avalonia.Rendering.Composition.Server
                     if (captureTiming)
                     {
                         var elapsed = StopwatchHelper.GetElapsedTime(startingTimestamp);
-                        RenderTimeGraph.AddFrameValue(elapsed.TotalMilliseconds);
+                        RenderTimeGraph?.AddFrameValue(elapsed.TotalMilliseconds);
                     }
 
                     DrawOverlays(targetContext);
@@ -220,14 +224,16 @@ namespace Avalonia.Rendering.Composition.Server
                     (Compositor.BatchObjectPool.CurrentUsage + Compositor.BatchObjectPool.CurrentPool) *
                     Compositor.BatchObjectPool.ArraySize *
                     IntPtr.Size), false);
-                FpsCounter.RenderFps(targetContext,
+                FpsCounter?.RenderFps(targetContext,
                     FormattableString.Invariant($"M:{managedMem} / N:{nativeMem} R:{RenderedVisuals:0000}"));
             }
 
             var top = 0.0;
 
-            void DrawTimeGraph(FrameTimeGraph graph)
+            void DrawTimeGraph(FrameTimeGraph? graph)
             {
+                if (graph == null)
+                    return;
                 top += 8.0;
                 targetContext.Transform = Matrix.CreateTranslation(Size.Width - graph.Size.Width - 8.0, top);
                 graph.Render(targetContext);
diff --git a/src/Avalonia.Base/Rendering/Composition/Server/ServerCompositionVisual.cs b/src/Avalonia.Base/Rendering/Composition/Server/ServerCompositionVisual.cs
index 853b90be5e..0eeffda123 100644
--- a/src/Avalonia.Base/Rendering/Composition/Server/ServerCompositionVisual.cs
+++ b/src/Avalonia.Base/Rendering/Composition/Server/ServerCompositionVisual.cs
@@ -58,7 +58,7 @@ namespace Avalonia.Rendering.Composition.Server
                 canvas.PushEffect(Effect);
             
             if (Opacity != 1)
-                canvas.PushOpacity(Opacity, boundsRect);
+                canvas.PushOpacity(Opacity, ClipToBounds ? boundsRect : null);
             if (ClipToBounds && !HandlesClipToBounds)
                 canvas.PushClip(Root!.SnapToDevicePixels(boundsRect));
             if (Clip != null) 
diff --git a/src/Avalonia.Base/Rendering/Composition/Server/ServerCompositor.cs b/src/Avalonia.Base/Rendering/Composition/Server/ServerCompositor.cs
index 8652ef223c..38969fa582 100644
--- a/src/Avalonia.Base/Rendering/Composition/Server/ServerCompositor.cs
+++ b/src/Avalonia.Base/Rendering/Composition/Server/ServerCompositor.cs
@@ -57,7 +57,8 @@ namespace Avalonia.Rendering.Composition.Server
 
         internal void UpdateServerTime() => ServerNow = Clock.Elapsed;
 
-        List<Batch> _reusableToCompleteList = new();
+        List<Batch> _reusableToNotifyProcessedList = new();
+        List<Batch> _reusableToNotifyRenderedList = new();
         void ApplyPendingBatches()
         {
             while (true)
@@ -100,7 +101,7 @@ namespace Avalonia.Rendering.Composition.Server
                     }
                 }
 
-                _reusableToCompleteList.Add(batch);
+                _reusableToNotifyProcessedList.Add(batch);
                 LastBatchId = batch.SequenceId;
             }
         }
@@ -135,17 +136,23 @@ namespace Avalonia.Rendering.Composition.Server
                 }
         }
 
-        void CompletePendingBatches()
+        void NotifyBatchesProcessed()
         {
-            foreach(var batch in _reusableToCompleteList)
-                batch.Complete();
-            _reusableToCompleteList.Clear();
-        }
+            foreach (var batch in _reusableToNotifyProcessedList) 
+                batch.NotifyProcessed();
 
-        bool IRenderLoopTask.NeedsUpdate => false;
+            foreach (var batch in _reusableToNotifyProcessedList)
+                _reusableToNotifyRenderedList.Add(batch);
 
-        void IRenderLoopTask.Update(TimeSpan time)
+            _reusableToNotifyProcessedList.Clear();
+        }
+        
+        void NotifyBatchesRendered()
         {
+            foreach (var batch in _reusableToNotifyRenderedList) 
+                batch.NotifyRendered();
+
+            _reusableToNotifyRenderedList.Clear();
         }
 
         public void Render()
@@ -159,8 +166,10 @@ namespace Avalonia.Rendering.Composition.Server
                 }
                 finally
                 {
+                    NotifyBatchesRendered();
                     _safeThread = null;
                 }
+                
             }
         }
         
@@ -168,7 +177,7 @@ namespace Avalonia.Rendering.Composition.Server
         {
             UpdateServerTime();
             ApplyPendingBatches();
-            CompletePendingBatches();
+            NotifyBatchesProcessed();
             
             foreach(var animation in _clockItems)
                 _clockItemsToUpdate.Add(animation);
diff --git a/src/Avalonia.Base/Rendering/Composition/Transport/Batch.cs b/src/Avalonia.Base/Rendering/Composition/Transport/Batch.cs
index 803ea809c0..992e5ba7b9 100644
--- a/src/Avalonia.Base/Rendering/Composition/Transport/Batch.cs
+++ b/src/Avalonia.Base/Rendering/Composition/Transport/Batch.cs
@@ -15,12 +15,13 @@ namespace Avalonia.Rendering.Composition.Transport
     {
         private static long _nextSequenceId = 1;
         private static ConcurrentBag<BatchStreamData> _pool = new();
-        private readonly TaskCompletionSource<int>? _tcs;
+        private readonly TaskCompletionSource<int> _acceptedTcs = new();
+        private readonly TaskCompletionSource<int> _renderedTcs = new();
+        
         public long SequenceId { get; }
         
-        public Batch(TaskCompletionSource<int>? tcs)
+        public Batch()
         {
-            _tcs = tcs;
             SequenceId = Interlocked.Increment(ref _nextSequenceId);
             if (!_pool.TryTake(out var lst))
                 lst = new BatchStreamData();
@@ -30,14 +31,17 @@ namespace Avalonia.Rendering.Composition.Transport
         
         public BatchStreamData Changes { get; private set; }
         public TimeSpan CommittedAt { get; set; }
+        public Task Processed => _acceptedTcs.Task;
+        public Task Rendered => _renderedTcs.Task;
         
-        public void Complete()
+        public void NotifyProcessed()
         {
             _pool.Add(Changes);
             Changes = null!;
 
-            _tcs?.TrySetResult(0);
+            _acceptedTcs.TrySetResult(0);
         }
-
+        
+        public void NotifyRendered() => _renderedTcs.TrySetResult(0);
     }
 }
diff --git a/src/Avalonia.Base/Rendering/Composition/Transport/BatchStreamArrayPool.cs b/src/Avalonia.Base/Rendering/Composition/Transport/BatchStreamArrayPool.cs
index 8916983a5c..222e9918d2 100644
--- a/src/Avalonia.Base/Rendering/Composition/Transport/BatchStreamArrayPool.cs
+++ b/src/Avalonia.Base/Rendering/Composition/Transport/BatchStreamArrayPool.cs
@@ -24,14 +24,17 @@ internal abstract class BatchStreamPoolBase<T> : IDisposable
     public int CurrentUsage => _usage;
     public int CurrentPool => _pool.Count;
 
-    public BatchStreamPoolBase(bool needsFinalize, Action<Func<bool>>? startTimer = null)
+    public BatchStreamPoolBase(bool needsFinalize, bool reclaimImmediately, Action<Func<bool>>? startTimer = null)
     {
         if(!needsFinalize)
             GC.SuppressFinalize(needsFinalize);
 
         var updateRef = new WeakReference<BatchStreamPoolBase<T>>(this);
-        if (AvaloniaLocator.Current.GetService<IPlatformThreadingInterface>() == null
-            && AvaloniaLocator.Current.GetService<IDispatcherImpl>() == null)
+        if (
+            reclaimImmediately 
+            || (
+            AvaloniaLocator.Current.GetService<IPlatformThreadingInterface>() == null
+            && AvaloniaLocator.Current.GetService<IDispatcherImpl>() == null))
             _reclaimImmediately = true;
         else
             StartUpdateTimer(startTimer, updateRef);
@@ -134,7 +137,8 @@ internal sealed class BatchStreamObjectPool<T> : BatchStreamPoolBase<T[]> where
 {
     public int ArraySize { get; }
 
-    public BatchStreamObjectPool(int arraySize = 128, Action<Func<bool>>? startTimer = null) : base(false, startTimer)
+    public BatchStreamObjectPool(bool reclaimImmediately = false, int arraySize = 128, Action<Func<bool>>? startTimer = null) 
+        : base(false, reclaimImmediately, startTimer)
     {
         ArraySize = arraySize;
     }
@@ -154,7 +158,8 @@ internal sealed class BatchStreamMemoryPool : BatchStreamPoolBase<IntPtr>
 {
     public int BufferSize { get; }
 
-    public BatchStreamMemoryPool(int bufferSize = 1024, Action<Func<bool>>? startTimer = null) : base(true, startTimer)
+    public BatchStreamMemoryPool(bool reclaimImmediately, int bufferSize = 1024, Action<Func<bool>>? startTimer = null) 
+        : base(true, reclaimImmediately, startTimer)
     {
         BufferSize = bufferSize;
     }
diff --git a/src/Avalonia.Base/Rendering/DefaultRenderTimer.cs b/src/Avalonia.Base/Rendering/DefaultRenderTimer.cs
index 7b0fecf675..74c8bd107a 100644
--- a/src/Avalonia.Base/Rendering/DefaultRenderTimer.cs
+++ b/src/Avalonia.Base/Rendering/DefaultRenderTimer.cs
@@ -1,4 +1,5 @@
 using System;
+using Avalonia.Metadata;
 using Avalonia.Platform;
 
 namespace Avalonia.Rendering
@@ -10,6 +11,7 @@ namespace Avalonia.Rendering
     /// This class may be overridden by platform implementations to use a specialized timer
     /// implementation.
     /// </remarks>
+    [PrivateApi]
     public class DefaultRenderTimer : IRenderTimer
     {
         private IRuntimePlatform? _runtime;
diff --git a/src/Avalonia.Base/Rendering/DirtyRects.cs b/src/Avalonia.Base/Rendering/DirtyRects.cs
deleted file mode 100644
index 610163191d..0000000000
--- a/src/Avalonia.Base/Rendering/DirtyRects.cs
+++ /dev/null
@@ -1,87 +0,0 @@
-using System.Collections;
-using System.Collections.Generic;
-
-namespace Avalonia.Rendering
-{
-    /// <summary>
-    /// Tracks dirty rectangles.
-    /// </summary>
-    internal class DirtyRects : IEnumerable<Rect>
-    {
-        private List<Rect> _rects = new List<Rect>();
-
-        /// <summary>
-        /// Gets a value indicating whether the collection of dirty rectangles is empty.
-        /// </summary>
-        public bool IsEmpty => _rects.Count == 0;
-
-        /// <summary>
-        /// Adds a dirty rectangle, extending an existing dirty rectangle if it intersects.
-        /// </summary>
-        /// <param name="rect">The dirt rectangle.</param>
-        /// <remarks>
-        /// We probably want to do this more intelligently because:
-        /// - Adding e.g. the top left quarter of a scene and the bottom left quarter of a scene
-        ///   will cause the whole scene to be invalidated if they overlap by a single pixel
-        /// - Adding two adjacent rectangles that don't overlap will not cause them to be 
-        /// coalesced
-        /// - It only coalesces the first intersecting rectangle found - one needs to
-        ///  call <see cref="Coalesce"/> at the end of the draw cycle to coalesce the rest.
-        /// </remarks>
-        public void Add(Rect rect)
-        {
-            if (rect.Width != 0 || rect.Height != 0)
-            {
-                for (var i = 0; i < _rects.Count; ++i)
-                {
-                    var r = _rects[i];
-
-                    if (r.Intersects(rect))
-                    {
-                        _rects[i] = r.Union(rect);
-                        return;
-                    }
-                }
-
-                _rects.Add(rect);
-            }
-        }
-
-        /// <summary>
-        /// Works around our flimsy dirt-rect coalescing algorithm.
-        /// </summary>
-        /// <remarks>
-        /// See the comments in <see cref="Add(Rect)"/>.
-        /// </remarks>
-        public void Coalesce()
-        {
-            for (var i = _rects.Count - 1; i >= 0; --i)
-            {
-                var a = _rects[i];
-
-                for (var j = 0; j < i; ++j)
-                {
-                    var b = _rects[j];
-
-                    if (i < _rects.Count && a.Intersects(b))
-                    {
-                        _rects[i] = _rects[i].Union(b);
-                        _rects.RemoveAt(i);
-                    }
-                }
-            }
-        }
-
-        /// <summary>
-        /// Gets the dirty rectangles.
-        /// </summary>
-        /// <returns>A collection of dirty rectangles</returns>
-        public IEnumerator<Rect> GetEnumerator() => _rects.GetEnumerator();
-
-        /// <summary>
-        /// Gets the dirty rectangles.
-        /// </summary>
-        /// <returns>A collection of dirty rectangles</returns>
-        IEnumerator IEnumerable.GetEnumerator() => _rects.GetEnumerator();
-    }
-}
diff --git a/src/Avalonia.Base/Rendering/DirtyVisuals.cs b/src/Avalonia.Base/Rendering/DirtyVisuals.cs
deleted file mode 100644
index dfadbdf614..0000000000
--- a/src/Avalonia.Base/Rendering/DirtyVisuals.cs
+++ /dev/null
@@ -1,104 +0,0 @@
-using System;
-using System.Collections;
-using System.Collections.Generic;
-using Avalonia.VisualTree;
-
-namespace Avalonia.Rendering
-{
-    /// <summary>
-    /// Stores a list of dirty visuals for an <see cref="IRenderer"/>.
-    /// </summary>
-    /// <remarks>
-    /// This class stores the dirty visuals for a scene, ordered by their distance to the root
-    /// visual. TODO: We probably want to put an upper limit on the number of visuals that can be
-    /// stored and if we reach that limit, assume all visuals are dirty.
-    /// </remarks>
-    internal class DirtyVisuals : IEnumerable<Visual>
-    {
-        private SortedDictionary<int, List<Visual>> _inner = new SortedDictionary<int, List<Visual>>();
-        private Dictionary<Visual, int> _index = new Dictionary<Visual, int>();
-        private int _enumerating;
-
-        /// <summary>
-        /// Gets the number of dirty visuals.
-        /// </summary>
-        public int Count => _index.Count;
-
-        /// <summary>
-        /// Adds a visual to the dirty list.
-        /// </summary>
-        /// <param name="visual">The dirty visual.</param>
-        public void Add(Visual visual)
-        {
-            if (_enumerating > 0)
-            {
-                throw new InvalidOperationException("Visual was invalidated during a render pass");
-            }
-
-            var distance = visual.CalculateDistanceFromAncestor((Visual?)visual.GetVisualRoot());
-
-            if (_index.TryGetValue(visual, out var existingDistance))
-            {
-                if (distance == existingDistance)
-                {
-                    return;
-                }
-
-                _inner[existingDistance].Remove(visual);
-                _index.Remove(visual);
-            }
-
-            if (!_inner.TryGetValue(distance, out var list))
-            {
-                list = new List<Visual>();
-                _inner.Add(distance, list);
-            }
-
-            list.Add(visual);
-            _index.Add(visual, distance);
-        }
-
-        /// <summary>
-        /// Clears the list.
-        /// </summary>
-        public void Clear()
-        {
-            if (_enumerating > 0)
-            {
-                throw new InvalidOperationException("Cannot clear while enumerating");
-            }
-
-            _inner.Clear();
-            _index.Clear();
-        }
-
-        /// <summary>
-        /// Gets the dirty visuals, in ascending order of distance to their root.
-        /// </summary>
-        /// <returns>A collection of visuals.</returns>
-        public IEnumerator<Visual> GetEnumerator()
-        {
-            _enumerating++;
-            try
-            {
-                foreach (var i in _inner)
-                {
-                    foreach (var j in i.Value)
-                    {
-                        yield return j;
-                    }
-                }
-            }
-            finally
-            {
-                _enumerating--;
-            }
-        }
-        
-        /// <summary>
-        /// Gets the dirty visuals, in ascending order of distance to their root.
-        /// </summary>
-        /// <returns>A collection of visuals.</returns>
-        IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
-    }
-}
diff --git a/src/Avalonia.Base/Rendering/DisplayDirtyRect.cs b/src/Avalonia.Base/Rendering/DisplayDirtyRect.cs
deleted file mode 100644
index 7a89e5b3cc..0000000000
--- a/src/Avalonia.Base/Rendering/DisplayDirtyRect.cs
+++ /dev/null
@@ -1,51 +0,0 @@
-using System;
-
-namespace Avalonia.Rendering
-{
-    /// <summary>
-    /// Holds the state for a dirty rect rendered when <see cref="IRenderer.SceneInvalidated"/> is set.
-    /// </summary>
-    internal class DisplayDirtyRect
-    {
-        public static readonly TimeSpan TimeToLive = TimeSpan.FromMilliseconds(250);
-
-        /// <summary>
-        /// Initializes a new instance of the <see cref="DisplayDirtyRect"/> class.
-        /// </summary>
-        /// <param name="rect">The dirt rect.</param>
-        public DisplayDirtyRect(Rect rect)
-        {
-            Rect = rect;
-            ResetLifetime();
-        }
-
-        /// <summary>
-        /// Gets the bounds of the dirty rectangle.
-        /// </summary>
-        public Rect Rect { get; }
-
-        /// <summary>
-        /// Gets the time at which the rectangle was made dirty.
-        /// </summary>
-        public DateTimeOffset Born { get; private set; }
-
-        /// <summary>
-        /// Gets the time at which the rectangle should no longer be displayed.
-        /// </summary>
-        public DateTimeOffset Dies { get; private set; }
-
-        /// <summary>
-        /// Gets the opacity at which to display the dirty rectangle.
-        /// </summary>
-        public double Opacity => (Dies - DateTimeOffset.UtcNow).TotalMilliseconds / TimeToLive.TotalMilliseconds;
-
-        /// <summary>
-        /// Resets the rectangle's lifetime.
-        /// </summary>
-        public void ResetLifetime()
-        {
-            Born = DateTimeOffset.UtcNow;
-            Dies = Born + TimeToLive;
-        }
-    }
-}
diff --git a/src/Avalonia.Base/Rendering/DisplayDirtyRects.cs b/src/Avalonia.Base/Rendering/DisplayDirtyRects.cs
deleted file mode 100644
index 2ffc1b4118..0000000000
--- a/src/Avalonia.Base/Rendering/DisplayDirtyRects.cs
+++ /dev/null
@@ -1,62 +0,0 @@
-using System;
-using System.Collections;
-using System.Collections.Generic;
-
-namespace Avalonia.Rendering
-{
-    /// <summary>
-    /// Holds a collection of <see cref="DisplayDirtyRect"/> objects and manages their aging.
-    /// </summary>
-    internal class DisplayDirtyRects : IEnumerable<DisplayDirtyRect>
-    {
-        private List<DisplayDirtyRect> _inner = new List<DisplayDirtyRect>();
-
-        /// <summary>
-        /// Adds new new dirty rect to the collection.
-        /// </summary>
-        /// <param name="rect"></param>
-        public void Add(Rect rect)
-        {
-            foreach (var r in _inner)
-            {
-                if (r.Rect == rect)
-                {
-                    r.ResetLifetime();
-                    return;
-                }
-            }
-
-            _inner.Add(new DisplayDirtyRect(rect));
-        }
-
-        /// <summary>
-        /// Removes dirty rects one they are no longer active.
-        /// </summary>
-        public void Tick()
-        {
-            var now = DateTimeOffset.UtcNow;
-
-            for (var i = _inner.Count - 1; i >= 0; --i)
-            {
-                var r = _inner[i];
-
-                if (now > r.Dies)
-                {
-                    _inner.RemoveAt(i);
-                }
-            }
-        }
-
-        /// <summary>
-        /// Gets the dirty rects.
-        /// </summary>
-        /// <returns>A collection of <see cref="DisplayDirtyRect"/> objects.</returns>
-        public IEnumerator<DisplayDirtyRect> GetEnumerator() => _inner.GetEnumerator();
-
-        /// <summary>
-        /// Gets the dirty rects.
-        /// </summary>
-        /// <returns>A collection of <see cref="DisplayDirtyRect"/> objects.</returns>
-        IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
-    }
-}
diff --git a/src/Avalonia.Base/Rendering/IDeferredRendererLock.cs b/src/Avalonia.Base/Rendering/IDeferredRendererLock.cs
deleted file mode 100644
index 1c6bd69158..0000000000
--- a/src/Avalonia.Base/Rendering/IDeferredRendererLock.cs
+++ /dev/null
@@ -1,11 +0,0 @@
-using System;
-using Avalonia.Metadata;
-
-namespace Avalonia.Rendering
-{
-    [Unstable]
-    public interface IDeferredRendererLock
-    {
-        IDisposable? TryLock();
-    }
-}
diff --git a/src/Avalonia.Base/Rendering/IRenderLoop.cs b/src/Avalonia.Base/Rendering/IRenderLoop.cs
index ebe683949d..bf2c221b03 100644
--- a/src/Avalonia.Base/Rendering/IRenderLoop.cs
+++ b/src/Avalonia.Base/Rendering/IRenderLoop.cs
@@ -10,7 +10,7 @@ namespace Avalonia.Rendering
     /// graph for visible windows.
     /// </remarks>
     [NotClientImplementable]
-    public interface IRenderLoop
+    internal interface IRenderLoop
     {
         /// <summary>
         /// Adds an update task.
diff --git a/src/Avalonia.Base/Rendering/IRenderLoopTask.cs b/src/Avalonia.Base/Rendering/IRenderLoopTask.cs
index 15f0afc797..f63855e651 100644
--- a/src/Avalonia.Base/Rendering/IRenderLoopTask.cs
+++ b/src/Avalonia.Base/Rendering/IRenderLoopTask.cs
@@ -3,10 +3,8 @@ using System.Threading.Tasks;
 
 namespace Avalonia.Rendering
 {
-    public interface IRenderLoopTask
+    internal interface IRenderLoopTask
     {
-        bool NeedsUpdate { get; }
-        void Update(TimeSpan time);
         void Render();
     }
 }
diff --git a/src/Avalonia.Base/Rendering/IRenderRoot.cs b/src/Avalonia.Base/Rendering/IRenderRoot.cs
index 09df7b7830..371d34b1f4 100644
--- a/src/Avalonia.Base/Rendering/IRenderRoot.cs
+++ b/src/Avalonia.Base/Rendering/IRenderRoot.cs
@@ -16,7 +16,9 @@ namespace Avalonia.Rendering
         /// <summary>
         /// Gets the renderer for the window.
         /// </summary>
-        IRenderer Renderer { get; }
+        internal IRenderer Renderer { get; }
+        
+        internal IHitTester HitTester { get; }
 
         /// <summary>
         /// The scaling factor to use in rendering.
diff --git a/src/Avalonia.Base/Rendering/IRenderTimer.cs b/src/Avalonia.Base/Rendering/IRenderTimer.cs
index 14fcffd6a9..396e84d492 100644
--- a/src/Avalonia.Base/Rendering/IRenderTimer.cs
+++ b/src/Avalonia.Base/Rendering/IRenderTimer.cs
@@ -6,7 +6,7 @@ namespace Avalonia.Rendering
     /// <summary>
     /// Defines the interface implemented by an application render timer.
     /// </summary>
-    [NotClientImplementable]
+    [PrivateApi]
     public interface IRenderTimer
     {
         /// <summary>
diff --git a/src/Avalonia.Base/Rendering/IRenderer.cs b/src/Avalonia.Base/Rendering/IRenderer.cs
index 7e32504e17..4cb79d803d 100644
--- a/src/Avalonia.Base/Rendering/IRenderer.cs
+++ b/src/Avalonia.Base/Rendering/IRenderer.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using Avalonia.Metadata;
 using Avalonia.Rendering.Composition;
 
 namespace Avalonia.Rendering
@@ -8,7 +9,7 @@ namespace Avalonia.Rendering
     /// <summary>
     /// Defines the interface for a renderer.
     /// </summary>
-    public interface IRenderer : IDisposable
+    internal interface IRenderer : IDisposable
     {
         /// <summary>
         /// Gets a value indicating whether the renderer should draw specific diagnostics.
@@ -29,31 +30,7 @@ namespace Avalonia.Rendering
         /// </summary>
         /// <param name="visual">The visual.</param>
         void AddDirty(Visual visual);
-
-        /// <summary>
-        /// Hit tests a location to find the visuals at the specified point.
-        /// </summary>
-        /// <param name="p">The point, in client coordinates.</param>
-        /// <param name="root">The root of the subtree to search.</param>
-        /// <param name="filter">
-        /// A filter predicate. If the predicate returns false then the visual and all its
-        /// children will be excluded from the results.
-        /// </param>
-        /// <returns>The visuals at the specified point, topmost first.</returns>
-        IEnumerable<Visual> HitTest(Point p, Visual root, Func<Visual, bool> filter);
-
-        /// <summary>
-        /// Hit tests a location to find first visual at the specified point.
-        /// </summary>
-        /// <param name="p">The point, in client coordinates.</param>
-        /// <param name="root">The root of the subtree to search.</param>
-        /// <param name="filter">
-        /// A filter predicate. If the predicate returns false then the visual and all its
-        /// children will be excluded from the results.
-        /// </param>
-        /// <returns>The visual at the specified point, topmost first.</returns>
-        Visual? HitTestFirst(Point p, Visual root, Func<Visual, bool> filter);
-
+        
         /// <summary>
         /// Informs the renderer that the z-ordering of a visual's children has changed.
         /// </summary>
@@ -88,11 +65,38 @@ namespace Avalonia.Rendering
         public ValueTask<object?> TryGetRenderInterfaceFeature(Type featureType);
     }
     
-    public interface IRendererWithCompositor : IRenderer
+    internal interface IRendererWithCompositor : IRenderer
     {
         /// <summary>
         /// The associated <see cref="Avalonia.Rendering.Composition.Compositor"/> object
         /// </summary>
         Compositor Compositor { get; }
     }
+
+    internal interface IHitTester
+    {
+        /// <summary>
+        /// Hit tests a location to find the visuals at the specified point.
+        /// </summary>
+        /// <param name="p">The point, in client coordinates.</param>
+        /// <param name="root">The root of the subtree to search.</param>
+        /// <param name="filter">
+        /// A filter predicate. If the predicate returns false then the visual and all its
+        /// children will be excluded from the results.
+        /// </param>
+        /// <returns>The visuals at the specified point, topmost first.</returns>
+        IEnumerable<Visual> HitTest(Point p, Visual root, Func<Visual, bool> filter);
+
+        /// <summary>
+        /// Hit tests a location to find first visual at the specified point.
+        /// </summary>
+        /// <param name="p">The point, in client coordinates.</param>
+        /// <param name="root">The root of the subtree to search.</param>
+        /// <param name="filter">
+        /// A filter predicate. If the predicate returns false then the visual and all its
+        /// children will be excluded from the results.
+        /// </param>
+        /// <returns>The visual at the specified point, topmost first.</returns>
+        Visual? HitTestFirst(Point p, Visual root, Func<Visual, bool> filter);
+    }
 }
diff --git a/src/Avalonia.Base/Rendering/IVisualBrushInitialize.cs b/src/Avalonia.Base/Rendering/IVisualBrushInitialize.cs
index b5ab8ed0bd..227e6c1f1f 100644
--- a/src/Avalonia.Base/Rendering/IVisualBrushInitialize.cs
+++ b/src/Avalonia.Base/Rendering/IVisualBrushInitialize.cs
@@ -8,7 +8,7 @@ namespace Avalonia.Rendering
     /// <see cref="VisualBrush"/>.
     /// </summary>
     [Unstable]
-    public interface IVisualBrushInitialize
+    internal interface IVisualBrushInitialize
     {
         /// <summary>
         /// Ensures that the control is ready to use as the visual in a visual brush.
diff --git a/src/Avalonia.Base/Rendering/ImmediateRenderer.cs b/src/Avalonia.Base/Rendering/ImmediateRenderer.cs
index 3462b1008a..37c5e0a2c6 100644
--- a/src/Avalonia.Base/Rendering/ImmediateRenderer.cs
+++ b/src/Avalonia.Base/Rendering/ImmediateRenderer.cs
@@ -96,7 +96,7 @@ namespace Avalonia.Rendering
                     }
 
                     using (context.PushTransform(m))
-                    using (context.PushOpacity(opacity, bounds))
+                    using (context.PushOpacity(opacity))
                     using (clipToBounds
 #pragma warning disable CS0618 // Type or member is obsolete
                         ? visual is IVisualWithRoundRectClip roundClipVisual
diff --git a/src/Avalonia.Base/Rendering/ManagedDeferredRendererLock.cs b/src/Avalonia.Base/Rendering/ManagedDeferredRendererLock.cs
deleted file mode 100644
index 0397a32bfd..0000000000
--- a/src/Avalonia.Base/Rendering/ManagedDeferredRendererLock.cs
+++ /dev/null
@@ -1,11 +0,0 @@
-using System;
-using System.Threading;
-using Avalonia.Utilities;
-
-namespace Avalonia.Rendering
-{
-    internal class ManagedDeferredRendererLock : DisposableLock, IDeferredRendererLock
-    {
-       
-    }
-}
diff --git a/src/Avalonia.Base/Rendering/RenderLoop.cs b/src/Avalonia.Base/Rendering/RenderLoop.cs
index 185f44d29a..aaecf5deaf 100644
--- a/src/Avalonia.Base/Rendering/RenderLoop.cs
+++ b/src/Avalonia.Base/Rendering/RenderLoop.cs
@@ -14,33 +14,38 @@ namespace Avalonia.Rendering
     /// The render loop is responsible for advancing the animation timer and updating the scene
     /// graph for visible windows.
     /// </remarks>
-    public class RenderLoop : IRenderLoop
+    internal class RenderLoop : IRenderLoop
     {
-        private readonly IDispatcher _dispatcher;
         private List<IRenderLoopTask> _items = new List<IRenderLoopTask>();
         private List<IRenderLoopTask> _itemsCopy = new List<IRenderLoopTask>();
-        private List<IRenderLoopTask> _updateItemsCopy = new List<IRenderLoopTask>();
         private IRenderTimer? _timer;
         private int _inTick;
         private int _inUpdate;
-
-        /// <summary>
-        /// Initializes a new instance of the <see cref="RenderLoop"/> class.
-        /// </summary>
-        public RenderLoop()
+        
+        public static IRenderLoop LocatorAutoInstance
         {
-            _dispatcher = Dispatcher.UIThread;
-        }
+            get
+            {
+                var loop = AvaloniaLocator.Current.GetService<IRenderLoop>();
+                if (loop == null)
+                {
+                    var timer = AvaloniaLocator.Current.GetRequiredService<IRenderTimer>();
+                    AvaloniaLocator.CurrentMutable.Bind<IRenderLoop>()
+                        .ToConstant(loop = new RenderLoop(timer));
+                }
 
+                return loop;
+            }
+        }
+        
         /// <summary>
         /// Initializes a new instance of the <see cref="RenderLoop"/> class.
         /// </summary>
         /// <param name="timer">The render timer.</param>
         /// <param name="dispatcher">The UI thread dispatcher.</param>
-        public RenderLoop(IRenderTimer timer, IDispatcher dispatcher)
+        public RenderLoop(IRenderTimer timer)
         {
             _timer = timer;
-            _dispatcher = dispatcher;
         }
 
         /// <summary>
@@ -96,53 +101,13 @@ namespace Avalonia.Rendering
             {
                 try
                 {
-                    bool needsUpdate = false;
-
+                    
                     lock (_items)
                     {
                         _itemsCopy.Clear();
                         _itemsCopy.AddRange(_items);
                     }
                     
-                    foreach (IRenderLoopTask item in _itemsCopy)
-                    {
-                        if (item.NeedsUpdate)
-                        {
-                            needsUpdate = true;
-
-                            break;
-                        }
-                    }
-
-                    if (needsUpdate &&
-                        Interlocked.CompareExchange(ref _inUpdate, 1, 0) == 0)
-                    {
-                        _dispatcher.Post(() =>
-                        {
-                            lock (_items)
-                            {
-                                _updateItemsCopy.Clear();
-                                _updateItemsCopy.AddRange(_items);
-                            }
-                            foreach (var item in _updateItemsCopy)
-                            {
-                                if (item.NeedsUpdate)
-                                {
-                                    try
-                                    {
-                                        item.Update(time);
-                                    }
-                                    catch (Exception ex)
-                                    {
-                                        Logger.TryGet(LogEventLevel.Error, LogArea.Visual)?.Log(this, "Exception in render update: {Error}", ex);
-                                    }
-                                }
-                            }
-                            _updateItemsCopy.Clear();
-
-                            Interlocked.Exchange(ref _inUpdate, 0);
-                        }, DispatcherPriority.Render);
-                    }
 
                     for (int i = 0; i < _itemsCopy.Count; i++)
                     {
diff --git a/src/Avalonia.Base/Rendering/SceneInvalidatedEventArgs.cs b/src/Avalonia.Base/Rendering/SceneInvalidatedEventArgs.cs
index cac4d1693a..fcccd9c752 100644
--- a/src/Avalonia.Base/Rendering/SceneInvalidatedEventArgs.cs
+++ b/src/Avalonia.Base/Rendering/SceneInvalidatedEventArgs.cs
@@ -5,7 +5,7 @@ namespace Avalonia.Rendering
     /// <summary>
     /// Provides data for the <see cref="IRenderer.SceneInvalidated"/> event.
     /// </summary>
-    public class SceneInvalidatedEventArgs : EventArgs
+    internal class SceneInvalidatedEventArgs : EventArgs
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="SceneInvalidatedEventArgs"/> class.
diff --git a/src/Avalonia.Base/Rendering/SleepLoopRenderTimer.cs b/src/Avalonia.Base/Rendering/SleepLoopRenderTimer.cs
index cd43a3ef20..3ad4ea94d0 100644
--- a/src/Avalonia.Base/Rendering/SleepLoopRenderTimer.cs
+++ b/src/Avalonia.Base/Rendering/SleepLoopRenderTimer.cs
@@ -1,9 +1,11 @@
 using System;
 using System.Diagnostics;
 using System.Threading;
+using Avalonia.Metadata;
 
 namespace Avalonia.Rendering
 {
+    [PrivateApi]
     public class SleepLoopRenderTimer : IRenderTimer
     {
         private Action<TimeSpan>? _tick;
diff --git a/src/Avalonia.Base/Rendering/UiThreadRenderTimer.cs b/src/Avalonia.Base/Rendering/UiThreadRenderTimer.cs
index 7f2eedc98c..06dc34c10a 100644
--- a/src/Avalonia.Base/Rendering/UiThreadRenderTimer.cs
+++ b/src/Avalonia.Base/Rendering/UiThreadRenderTimer.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Diagnostics;
+using Avalonia.Metadata;
 using Avalonia.Reactive;
 using Avalonia.Threading;
 
@@ -8,6 +9,7 @@ namespace Avalonia.Rendering
     /// <summary>
     /// Render timer that ticks on UI thread. Useful for debugging or bootstrapping on new platforms 
     /// </summary>
+    [PrivateApi]
     public class UiThreadRenderTimer : DefaultRenderTimer
     {
         /// <summary>
@@ -32,7 +34,7 @@ namespace Avalonia.Rendering
                     return false;
                 tick(st.Elapsed);
                 return !cancelled;
-            }, TimeSpan.FromSeconds(1.0 / FramesPerSecond), DispatcherPriority.Render);
+            }, TimeSpan.FromSeconds(1.0 / FramesPerSecond), DispatcherPriority.UiThreadRender);
             return Disposable.Create(() => cancelled = true);
         }
     }
diff --git a/src/Avalonia.Base/Rotate3DTransform.cs b/src/Avalonia.Base/Rotate3DTransform.cs
index 2de33889c8..95f5d17740 100644
--- a/src/Avalonia.Base/Rotate3DTransform.cs
+++ b/src/Avalonia.Base/Rotate3DTransform.cs
@@ -7,7 +7,7 @@ namespace Avalonia.Media;
 /// <summary>
 ///  Non-Affine 3D transformation for rotating a visual around a definable axis
 /// </summary>
-public class Rotate3DTransform : Transform
+public sealed class Rotate3DTransform : Transform
 {
     private readonly bool _isInitializing;
     
diff --git a/src/Avalonia.Base/Threading/Dispatcher.Queue.cs b/src/Avalonia.Base/Threading/Dispatcher.Queue.cs
index 78a0740e56..829ab4cf87 100644
--- a/src/Avalonia.Base/Threading/Dispatcher.Queue.cs
+++ b/src/Avalonia.Base/Threading/Dispatcher.Queue.cs
@@ -83,6 +83,11 @@ public partial class Dispatcher
         {
         }
     }
+
+    internal static void ResetBeforeUnitTests()
+    {
+        s_uiThread = null;
+    }
     
     internal static void ResetForUnitTests()
     {
diff --git a/src/Avalonia.Base/Threading/DispatcherPriority.cs b/src/Avalonia.Base/Threading/DispatcherPriority.cs
index a43dd8e4a2..9fe7056abd 100644
--- a/src/Avalonia.Base/Threading/DispatcherPriority.cs
+++ b/src/Avalonia.Base/Threading/DispatcherPriority.cs
@@ -1,5 +1,6 @@
 using System;
 using System.ComponentModel;
+using Avalonia.Metadata;
 
 namespace Avalonia.Threading
 {
@@ -79,29 +80,39 @@ namespace Avalonia.Threading
         public static readonly DispatcherPriority Loaded = new(Default + 1);
 
         /// <summary>
-        /// The job will be processed with the same priority as render.
+        /// A special priority for platforms with UI render timer or for forced full rasterization requests
         /// </summary>
-        public static readonly DispatcherPriority Render = new(Loaded + 1);
+        [PrivateApi]
+        public static readonly DispatcherPriority UiThreadRender = new(Loaded + 1);
 
         /// <summary>
-        /// The job will be processed with the same priority as composition updates.
+        /// A special priority to synchronize native control host positions, IME, etc
+        /// We should probably have a better API for that, so the priority is internal
         /// </summary>
-        public static readonly DispatcherPriority Composition = new(Render + 1);
-
+        internal static readonly DispatcherPriority AfterRender = new(UiThreadRender + 1);
+        
         /// <summary>
-        /// The job will be processed with before composition updates.
+        /// The job will be processed with the same priority as render.
         /// </summary>
-        public static readonly DispatcherPriority PreComposition = new(Composition + 1);
-
+        public static readonly DispatcherPriority Render = new(AfterRender + 1);
+        
         /// <summary>
-        /// The job will be processed with the same priority as layout.
+        /// A special platform hook for jobs to be executed before the normal render cycle
         /// </summary>
-        public static readonly DispatcherPriority Layout = new(PreComposition + 1);
-
+        [PrivateApi]
+        public static readonly DispatcherPriority BeforeRender = new(Render + 1);
+        
+        /// <summary>
+        /// A special priority for platforms that resize the render target in asynchronous-ish matter,
+        /// should be changed into event grouping in the platform backend render
+        /// </summary>
+        [PrivateApi]
+        public static readonly DispatcherPriority AsyncRenderTargetResize = new(BeforeRender + 1);
+        
         /// <summary>
         /// The job will be processed with the same priority as data binding.
         /// </summary>
-        [Obsolete("WPF compatibility"), EditorBrowsable(EditorBrowsableState.Never)] public static readonly DispatcherPriority DataBind = new(Layout);
+        [Obsolete("WPF compatibility"), EditorBrowsable(EditorBrowsableState.Never)] public static readonly DispatcherPriority DataBind = new(Render);
         
         /// <summary>
         /// The job will be processed with normal priority.
@@ -183,12 +194,16 @@ namespace Avalonia.Threading
                 return nameof(Default);
             if (this == Loaded)
                 return nameof(Loaded);
+            if (this == UiThreadRender)
+                return nameof(UiThreadRender);
+            if (this == AfterRender)
+                return nameof(AfterRender);
             if (this == Render)
                 return nameof(Render);
-            if (this == Composition)
-                return nameof(Composition);
-            if (this == PreComposition)
-                return nameof(PreComposition);
+            if (this == BeforeRender)
+                return nameof(BeforeRender);
+            if (this == AsyncRenderTargetResize)
+                return nameof(AsyncRenderTargetResize);
             if (this == DataBind)
                 return nameof(DataBind);
             if (this == Normal)
diff --git a/src/Avalonia.Base/VisualTree/IVisualWithRoundRectClip.cs b/src/Avalonia.Base/VisualTree/IVisualWithRoundRectClip.cs
index 0079515a63..d85f50b591 100644
--- a/src/Avalonia.Base/VisualTree/IVisualWithRoundRectClip.cs
+++ b/src/Avalonia.Base/VisualTree/IVisualWithRoundRectClip.cs
@@ -3,14 +3,11 @@ using System.ComponentModel;
 
 namespace Avalonia.VisualTree
 {
-    [Obsolete("Internal API, will be removed in future versions, you've been warned"), EditorBrowsable(EditorBrowsableState.Never)]
-    public interface IVisualWithRoundRectClip
+    internal interface IVisualWithRoundRectClip
     {
         /// <summary>
         /// Gets a value indicating the corner radius of control's clip bounds
         /// </summary>
-        [Obsolete("Internal API, will be removed in future versions, you've been warned"), EditorBrowsable(EditorBrowsableState.Never)]
         CornerRadius ClipToBoundsRadius { get; }
-
     }
 }
diff --git a/src/Avalonia.Base/VisualTree/VisualExtensions.cs b/src/Avalonia.Base/VisualTree/VisualExtensions.cs
index cc372f7c39..b3cdd70fa0 100644
--- a/src/Avalonia.Base/VisualTree/VisualExtensions.cs
+++ b/src/Avalonia.Base/VisualTree/VisualExtensions.cs
@@ -305,7 +305,7 @@ namespace Avalonia.VisualTree
 
             if (rootPoint.HasValue)
             {
-                return root.Renderer.HitTestFirst(rootPoint.Value, visual, filter);
+                return root.HitTester.HitTestFirst(rootPoint.Value, visual, filter);
             }
 
             return null;
@@ -354,7 +354,7 @@ namespace Avalonia.VisualTree
 
             if (rootPoint.HasValue)
             {
-                return root.Renderer.HitTest(rootPoint.Value, visual, filter);
+                return root.HitTester.HitTest(rootPoint.Value, visual, filter);
             }
 
             return Enumerable.Empty<Visual>();
diff --git a/src/Avalonia.Build.Tasks/GenerateAvaloniaResourcesTask.cs b/src/Avalonia.Build.Tasks/GenerateAvaloniaResourcesTask.cs
index 264a86b014..620cd4723d 100644
--- a/src/Avalonia.Build.Tasks/GenerateAvaloniaResourcesTask.cs
+++ b/src/Avalonia.Build.Tasks/GenerateAvaloniaResourcesTask.cs
@@ -127,7 +127,7 @@ namespace Avalonia.Build.Tasks
 
         public bool Execute()
         {
-            Enum.TryParse<MessageImportance>(ReportImportance, out _reportImportance);
+            Enum.TryParse(ReportImportance, true, out _reportImportance);
 
             BuildEngine.LogMessage($"GenerateAvaloniaResourcesTask -> Root: {Root}, {Resources?.Count()} resources, Output:{Output}", _reportImportance < MessageImportance.Low ? MessageImportance.High : _reportImportance);
             var resources = BuildResourceSources();
diff --git a/src/Avalonia.Build.Tasks/XamlCompilerTaskExecutor.cs b/src/Avalonia.Build.Tasks/XamlCompilerTaskExecutor.cs
index d71070e818..1b611db62b 100644
--- a/src/Avalonia.Build.Tasks/XamlCompilerTaskExecutor.cs
+++ b/src/Avalonia.Build.Tasks/XamlCompilerTaskExecutor.cs
@@ -288,6 +288,24 @@ namespace Avalonia.Build.Tasks
                             if (precompileText != "true")
                                 throw new XamlParseException("Invalid value for x:Precompile", precompileDirective);
                         }
+
+                        var classModifierDirective = initialRoot.Children.OfType<XamlAstXmlDirective>()
+                            .FirstOrDefault(d => d.Namespace == XamlNamespaces.Xaml2006 && d.Name == "ClassModifier");
+                        bool? classModifierPublic = null;
+                        if (classModifierDirective != null)
+                        {
+                            var classModifierText = (classModifierDirective.Values[0] as XamlAstTextNode)?.Text.Trim()
+                                .ToLowerInvariant();
+                            if ("Public".Equals(classModifierText, StringComparison.OrdinalIgnoreCase))
+                                classModifierPublic = true;
+                            // XAML spec uses "Public" and "NotPublic" values,
+                            // When WPF documentation uses "public" and "internal".
+                            else if ("NotPublic".Equals(classModifierText, StringComparison.OrdinalIgnoreCase)
+                                     || "Internal".Equals(classModifierText, StringComparison.OrdinalIgnoreCase))
+                                classModifierPublic = false;
+                            else
+                                throw new XamlParseException("Invalid value for x:ClassModifier. Expected value are: Public, NotPublic (internal).", precompileDirective);
+                        }
                         
                         var classDirective = initialRoot.Children.OfType<XamlAstXmlDirective>()
                             .FirstOrDefault(d => d.Namespace == XamlNamespaces.Xaml2006 && d.Name == "Class");
@@ -297,8 +315,21 @@ namespace Avalonia.Build.Tasks
                             if (classDirective.Values.Count != 1 || !(classDirective.Values[0] is XamlAstTextNode tn))
                                 throw new XamlParseException("x:Class should have a string value", classDirective);
                             classType = typeSystem.TargetAssembly.FindType(tn.Text);
+
                             if (classType == null)
                                 throw new XamlParseException($"Unable to find type `{tn.Text}`", classDirective);
+
+                            var isClassPublic = typeSystem.GetTypeReference(classType).Resolve().IsPublic;
+                            classModifierPublic ??= isClassPublic;
+
+                            // We do not really need x:ClassModifier support for x:Class, but we can at least use it for validation here.
+                            if (classModifierPublic != isClassPublic)
+                            {
+                                throw new XamlParseException(
+                                    "XAML file x:ClassModifier doesn't match the x:Class type modifiers.",
+                                    precompileDirective);
+                            }
+                            
                             compiler.OverrideRootType(parsed,
                                 new XamlAstClrTypeReference(classDirective, classType, false));
                             initialRoot.Children.Remove(classDirective);
@@ -312,6 +343,8 @@ namespace Avalonia.Build.Tasks
                         var classTypeDefinition =
                             classType == null ? null : typeSystem.GetTypeReference(classType).Resolve();
 
+                        // All XAML files are public by default.
+                        classModifierPublic ??= true;
 
                         var populateBuilder = classTypeDefinition == null ?
                             builder :
@@ -319,10 +352,11 @@ namespace Avalonia.Build.Tasks
 
                         ((List<XamlDocumentResource>)parsedXamlDocuments).Add(new XamlDocumentResource(
                             parsed, res.Uri, res, classType,
+                            classModifierPublic.Value,
                             populateBuilder,
                             compiler.DefinePopulateMethod(populateBuilder, parsed, populateName,
-                                classTypeDefinition == null),
-                            buildName == null ? null : compiler.DefineBuildMethod(builder, parsed, buildName, true)));
+                                classTypeDefinition == null && classModifierPublic.Value),
+                            buildName == null ? null : compiler.DefineBuildMethod(builder, parsed, buildName, classModifierPublic.Value)));
                     }
                     catch (Exception e)
                     {
@@ -367,8 +401,7 @@ namespace Avalonia.Build.Tasks
                             contextClass,
                             document.PopulateMethod,
                             document.BuildMethod,
-                            builder.DefineSubType(compilerConfig.WellKnownTypes.Object, "NamespaceInfo:" + res.Name,
-                                true),
+                            builder.DefineSubType(compilerConfig.WellKnownTypes.Object, "NamespaceInfo:" + res.Name, true),
                             (closureName, closureBaseType) =>
                                 populateBuilder.DefineSubType(closureBaseType, closureName, false),
                             (closureName, returnType, parameterTypes) =>
@@ -502,7 +535,8 @@ namespace Avalonia.Build.Tasks
 
                         }
 
-                        if (document.BuildMethod != null || classTypeDefinition != null)
+                        if (document.IsPublic
+                            && (document.BuildMethod != null || classTypeDefinition != null))
                         {
                             var compiledBuildMethod = document.BuildMethod == null ?
                                 null :
diff --git a/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorPicker.xaml b/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorPicker.xaml
index f3100a648a..104314e54f 100644
--- a/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorPicker.xaml
+++ b/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorPicker.xaml
@@ -1,7 +1,8 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:controls="using:Avalonia.Controls"
-                    xmlns:primitives="using:Avalonia.Controls.Primitives">
+                    xmlns:primitives="using:Avalonia.Controls.Primitives"
+                    x:ClassModifier="internal">
 
   <ControlTheme x:Key="{x:Type ColorPicker}"
                 TargetType="ColorPicker">
diff --git a/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorPreviewer.xaml b/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorPreviewer.xaml
index fabc5d0349..520e6e8db3 100644
--- a/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorPreviewer.xaml
+++ b/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorPreviewer.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:pc="using:Avalonia.Controls.Primitives.Converters">
+                    xmlns:pc="using:Avalonia.Controls.Primitives.Converters"
+                    x:ClassModifier="internal">
 
   <pc:AccentColorConverter x:Key="AccentColorConverter" />
   <x:Double x:Key="ColorPreviewerAccentSectionWidth">80</x:Double>
diff --git a/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorSlider.xaml b/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorSlider.xaml
index 789473571b..edc6246ddd 100644
--- a/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorSlider.xaml
+++ b/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorSlider.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
 
   <!-- Note that the Slider thumb should generally follow the overall Slider dimensions.
        Therefore, there are not currently separate resources to control it. -->
diff --git a/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorSpectrum.xaml b/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorSpectrum.xaml
index ebbb006fd1..c9972125a0 100644
--- a/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorSpectrum.xaml
+++ b/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorSpectrum.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:controls="using:Avalonia.Controls">
+                    xmlns:controls="using:Avalonia.Controls"
+                    x:ClassModifier="internal">
 
   <ControlTheme x:Key="{x:Type ColorSpectrum}"
                 TargetType="ColorSpectrum">
diff --git a/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorView.xaml b/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorView.xaml
index 8793467b36..9ca55566f3 100644
--- a/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorView.xaml
+++ b/src/Avalonia.Controls.ColorPicker/Themes/Fluent/ColorView.xaml
@@ -4,7 +4,8 @@
                     xmlns:converters="using:Avalonia.Controls.Converters"
                     xmlns:primitives="using:Avalonia.Controls.Primitives"
                     xmlns:pc="using:Avalonia.Controls.Primitives.Converters"
-                    xmlns:globalization="using:System.Globalization">
+                    xmlns:globalization="using:System.Globalization"
+                    x:ClassModifier="internal">
 
   <pc:ContrastBrushConverter x:Key="ContrastBrushConverter" />
   <converters:ColorToDisplayNameConverter x:Key="ColorToDisplayNameConverter" />
diff --git a/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorPicker.xaml b/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorPicker.xaml
index d9ba8bb9d2..c20f7935f4 100644
--- a/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorPicker.xaml
+++ b/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorPicker.xaml
@@ -1,7 +1,8 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:controls="using:Avalonia.Controls"
-                    xmlns:primitives="using:Avalonia.Controls.Primitives">
+                    xmlns:primitives="using:Avalonia.Controls.Primitives"
+                    x:ClassModifier="internal">
 
   <ControlTheme x:Key="{x:Type ColorPicker}"
                 TargetType="ColorPicker">
diff --git a/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorPreviewer.xaml b/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorPreviewer.xaml
index 9e123b2a1f..23f0b34ddd 100644
--- a/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorPreviewer.xaml
+++ b/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorPreviewer.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:pc="using:Avalonia.Controls.Primitives.Converters">
+                    xmlns:pc="using:Avalonia.Controls.Primitives.Converters"
+                    x:ClassModifier="internal">
 
   <pc:AccentColorConverter x:Key="AccentColorConverter" />
   <x:Double x:Key="ColorPreviewerAccentSectionWidth">80</x:Double>
diff --git a/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorSlider.xaml b/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorSlider.xaml
index 472f1ca100..6b4ad68275 100644
--- a/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorSlider.xaml
+++ b/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorSlider.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
 
   <!-- Note that the Slider thumb should generally follow the overall Slider dimensions.
        Therefore, there are not currently separate resources to control it. -->
diff --git a/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorSpectrum.xaml b/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorSpectrum.xaml
index a7ad56d8b4..101a06ccb9 100644
--- a/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorSpectrum.xaml
+++ b/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorSpectrum.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:controls="using:Avalonia.Controls">
+                    xmlns:controls="using:Avalonia.Controls"
+                    x:ClassModifier="internal">
 
   <ControlTheme x:Key="{x:Type ColorSpectrum}"
                 TargetType="ColorSpectrum">
diff --git a/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorView.xaml b/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorView.xaml
index d4f02933f2..994a5e1bbc 100644
--- a/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorView.xaml
+++ b/src/Avalonia.Controls.ColorPicker/Themes/Simple/ColorView.xaml
@@ -4,7 +4,8 @@
                     xmlns:converters="using:Avalonia.Controls.Converters"
                     xmlns:primitives="using:Avalonia.Controls.Primitives"
                     xmlns:pc="using:Avalonia.Controls.Primitives.Converters"
-                    xmlns:globalization="using:System.Globalization">
+                    xmlns:globalization="using:System.Globalization"
+                    x:ClassModifier="internal">
 
   <pc:ContrastBrushConverter x:Key="ContrastBrushConverter" />
   <converters:ColorToDisplayNameConverter x:Key="ColorToDisplayNameConverter" />
diff --git a/src/Avalonia.Controls/Application.cs b/src/Avalonia.Controls/Application.cs
index e907fd5988..b98ad123f1 100644
--- a/src/Avalonia.Controls/Application.cs
+++ b/src/Avalonia.Controls/Application.cs
@@ -8,6 +8,7 @@ using Avalonia.Data;
 using Avalonia.Input;
 using Avalonia.Input.Platform;
 using Avalonia.Input.Raw;
+using Avalonia.Media;
 using Avalonia.Platform;
 using Avalonia.Rendering;
 using Avalonia.Styling;
@@ -117,25 +118,13 @@ namespace Avalonia
         /// </value>
         public DataTemplates DataTemplates => _dataTemplates ?? (_dataTemplates = new DataTemplates());
 
-        /// <summary>
-        /// Gets the application's focus manager.
-        /// </summary>
-        /// <value>
-        /// The application's focus manager.
-        /// </value>
-        public IFocusManager? FocusManager
-        {
-            get;
-            private set;
-        }
-
         /// <summary>
         /// Gets the application's input manager.
         /// </summary>
         /// <value>
         /// The application's input manager.
         /// </value>
-        public InputManager? InputManager
+        internal InputManager? InputManager
         {
             get;
             private set;
@@ -237,7 +226,7 @@ namespace Avalonia
         public virtual void RegisterServices()
         {
             AvaloniaSynchronizationContext.InstallIfNeeded();
-            FocusManager = new FocusManager();
+            var focusManager = new FocusManager();
             InputManager = new InputManager();
 
             var settings = AvaloniaLocator.Current.GetRequiredService<IPlatformSettings>();
@@ -249,7 +238,7 @@ namespace Avalonia
                 .Bind<IGlobalDataTemplates>().ToConstant(this)
                 .Bind<IGlobalStyles>().ToConstant(this)
                 .Bind<IThemeVariantHost>().ToConstant(this)
-                .Bind<IFocusManager>().ToConstant(FocusManager)
+                .Bind<IFocusManager>().ToConstant(focusManager)
                 .Bind<IInputManager>().ToConstant(InputManager)
                 .Bind<IKeyboardNavigationHandler>().ToTransient<KeyboardNavigationHandler>()
                 .Bind<IDragDropDevice>().ToConstant(DragDropDevice.Instance);
@@ -259,10 +248,8 @@ namespace Avalonia
                 AvaloniaLocator.CurrentMutable
                     .Bind<IPlatformDragSource>().ToTransient<InProcessDragSource>();
 
-            var clock = new RenderLoopClock();
-            AvaloniaLocator.CurrentMutable
-                .Bind<IGlobalClock>().ToConstant(clock)
-                .GetService<IRenderLoop>()?.Add(clock);
+            AvaloniaLocator.CurrentMutable.Bind<IGlobalClock>()
+                .ToConstant(MediaContext.Instance.Clock);
         }
 
         public virtual void OnFrameworkInitializationCompleted()
diff --git a/src/Avalonia.Controls/Automation/Peers/ControlAutomationPeer.cs b/src/Avalonia.Controls/Automation/Peers/ControlAutomationPeer.cs
index c55bd0f3e5..756951667b 100644
--- a/src/Avalonia.Controls/Automation/Peers/ControlAutomationPeer.cs
+++ b/src/Avalonia.Controls/Automation/Peers/ControlAutomationPeer.cs
@@ -31,11 +31,31 @@ namespace Avalonia.Automation.Peers
             return CreatePeerForElement(element);
         }
 
+        /// <summary>
+        /// Gets the <see cref="AutomationPeer"/> for a <see cref="Control"/>, creating it if
+        /// necessary.
+        /// </summary>
+        /// <param name="element">The control.</param>
+        /// <returns>The automation peer.</returns>
+        /// <remarks>
+        /// Despite the name (which comes from the analogous WPF API), this method does not create
+        /// a new peer if one already exists: instead it returns the existing peer.
+        /// </remarks>
         public static AutomationPeer CreatePeerForElement(Control element)
         {
             return element.GetOrCreateAutomationPeer();
         }
 
+        /// <summary>
+        /// Gets an existing <see cref="AutomationPeer"/> for a <see cref="Control"/>.
+        /// </summary>
+        /// <param name="element">The control.</param>
+        /// <returns>The automation peer if already created; otherwise null.</returns>
+        /// <remarks>
+        /// To ensure that a peer is created, use <see cref="CreatePeerForElement(Control)"/>.
+        /// </remarks>
+        public static AutomationPeer? FromElement(Control element) => element.GetAutomationPeer();
+
         protected override void BringIntoViewCore() => Owner.BringIntoView();
 
         protected override IReadOnlyList<AutomationPeer> GetOrCreateChildrenCore()
diff --git a/src/Avalonia.Controls/Avalonia.Controls.csproj b/src/Avalonia.Controls/Avalonia.Controls.csproj
index 3f1753a4d3..304454777f 100644
--- a/src/Avalonia.Controls/Avalonia.Controls.csproj
+++ b/src/Avalonia.Controls/Avalonia.Controls.csproj
@@ -13,6 +13,8 @@
 
   <ItemGroup Label="InternalsVisibleTo">
     <InternalsVisibleTo Include="Avalonia.Controls.ItemsRepeater, PublicKey=$(AvaloniaPublicKey)" />
+    <InternalsVisibleTo Include="Avalonia.UnitTests, PublicKey=$(AvaloniaPublicKey)" />
+    <InternalsVisibleTo Include="Avalonia.Base.UnitTests, PublicKey=$(AvaloniaPublicKey)" />
     <InternalsVisibleTo Include="Avalonia.Controls.UnitTests, PublicKey=$(AvaloniaPublicKey)" />
     <InternalsVisibleTo Include="Avalonia.Markup.UnitTests, PublicKey=$(AvaloniaPublicKey)" />
     <InternalsVisibleTo Include="Avalonia.DesignerSupport, PublicKey=$(AvaloniaPublicKey)" />
diff --git a/src/Avalonia.Controls/Border.cs b/src/Avalonia.Controls/Border.cs
index 78ba23c1dd..e7373a813e 100644
--- a/src/Avalonia.Controls/Border.cs
+++ b/src/Avalonia.Controls/Border.cs
@@ -47,30 +47,6 @@ namespace Avalonia.Controls
         public static readonly StyledProperty<BoxShadows> BoxShadowProperty =
             AvaloniaProperty.Register<Border, BoxShadows>(nameof(BoxShadow));
 
-        /// <summary>
-        /// Defines the <see cref="BorderDashOffset"/> property.
-        /// </summary>
-        public static readonly StyledProperty<double> BorderDashOffsetProperty =
-            AvaloniaProperty.Register<Border, double>(nameof(BorderDashOffset));
-
-        /// <summary>
-        /// Defines the <see cref="BorderDashArray"/> property.
-        /// </summary>
-        public static readonly StyledProperty<AvaloniaList<double>?> BorderDashArrayProperty =
-            AvaloniaProperty.Register<Border, AvaloniaList<double>?>(nameof(BorderDashArray));
-
-        /// <summary>
-        /// Defines the <see cref="BorderLineCap"/> property.
-        /// </summary>
-        public static readonly StyledProperty<PenLineCap> BorderLineCapProperty =
-            AvaloniaProperty.Register<Border, PenLineCap>(nameof(BorderLineCap), PenLineCap.Flat);
-
-        /// <summary>
-        /// Defines the <see cref="BorderLineJoin"/> property.
-        /// </summary>
-        public static readonly StyledProperty<PenLineJoin> BorderLineJoinProperty =
-            AvaloniaProperty.Register<Border, PenLineJoin>(nameof(BorderLineJoin), PenLineJoin.Miter);
-
         private readonly BorderRenderHelper _borderRenderHelper = new BorderRenderHelper();
         private Thickness? _layoutThickness;
         private double _scale;
@@ -86,10 +62,6 @@ namespace Avalonia.Controls
                 BorderBrushProperty,
                 BorderThicknessProperty,
                 CornerRadiusProperty,
-                BorderDashArrayProperty,
-                BorderLineCapProperty,
-                BorderLineJoinProperty,
-                BorderDashOffsetProperty,
                 BoxShadowProperty);
             AffectsMeasure<Border>(BorderThicknessProperty);
         }
@@ -115,8 +87,8 @@ namespace Avalonia.Controls
         /// </summary>
         public IBrush? Background
         {
-            get { return GetValue(BackgroundProperty); }
-            set { SetValue(BackgroundProperty, value); }
+            get => GetValue(BackgroundProperty);
+            set => SetValue(BackgroundProperty, value);
         }
 
         /// <summary>
@@ -124,17 +96,8 @@ namespace Avalonia.Controls
         /// </summary>
         public IBrush? BorderBrush
         {
-            get { return GetValue(BorderBrushProperty); }
-            set { SetValue(BorderBrushProperty, value); }
-        }
-
-        /// <summary>
-        /// Gets or sets a collection of <see cref="double"/> values that indicate the pattern of dashes and gaps that is used to outline shapes.
-        /// </summary>
-        public AvaloniaList<double>? BorderDashArray
-        {
-            get { return GetValue(BorderDashArrayProperty); }
-            set { SetValue(BorderDashArrayProperty, value); }
+            get => GetValue(BorderBrushProperty);
+            set => SetValue(BorderBrushProperty, value);
         }
 
         /// <summary>
@@ -142,35 +105,8 @@ namespace Avalonia.Controls
         /// </summary>
         public Thickness BorderThickness
         {
-            get { return GetValue(BorderThicknessProperty); }
-            set { SetValue(BorderThicknessProperty, value); }
-        }
-
-        /// <summary>
-        /// Gets or sets a value that specifies the distance within the dash pattern where a dash begins.
-        /// </summary>
-        public double BorderDashOffset
-        {
-            get { return GetValue(BorderDashOffsetProperty); }
-            set { SetValue(BorderDashOffsetProperty, value); }
-        }
-
-        /// <summary>
-        /// Gets or sets a <see cref="PenLineCap"/> enumeration value that describes the shape at the ends of a line.
-        /// </summary>
-        public PenLineCap BorderLineCap
-        {
-            get { return GetValue(BorderLineCapProperty); }
-            set { SetValue(BorderLineCapProperty, value); }
-        }
-
-        /// <summary>
-        /// Gets or sets a <see cref="PenLineJoin"/> enumeration value that specifies the type of join that is used at the vertices of a Shape.
-        /// </summary>
-        public PenLineJoin BorderLineJoin
-        {
-            get { return GetValue(BorderLineJoinProperty); }
-            set { SetValue(BorderLineJoinProperty, value); }
+            get => GetValue(BorderThicknessProperty);
+            set => SetValue(BorderThicknessProperty, value);
         }
 
         /// <summary>
@@ -178,8 +114,8 @@ namespace Avalonia.Controls
         /// </summary>
         public CornerRadius CornerRadius
         {
-            get { return GetValue(CornerRadiusProperty); }
-            set { SetValue(CornerRadiusProperty, value); }
+            get => GetValue(CornerRadiusProperty);
+            set => SetValue(CornerRadiusProperty, value);
         }
 
         /// <summary>
@@ -227,8 +163,14 @@ namespace Avalonia.Controls
         /// <param name="context">The drawing context.</param>
         public sealed override void Render(DrawingContext context)
         {
-            _borderRenderHelper.Render(context, Bounds.Size, LayoutThickness, CornerRadius, Background, BorderBrush,
-                BoxShadow, BorderDashOffset, BorderLineCap, BorderLineJoin, BorderDashArray);
+            _borderRenderHelper.Render(
+                context,
+                Bounds.Size,
+                LayoutThickness,
+                CornerRadius,
+                Background,
+                BorderBrush,
+                BoxShadow);
         }
 
         /// <summary>
diff --git a/src/Avalonia.Controls/Calendar/CalendarButton.cs b/src/Avalonia.Controls/Calendar/CalendarButton.cs
index d8672cbf18..b35298b101 100644
--- a/src/Avalonia.Controls/Calendar/CalendarButton.cs
+++ b/src/Avalonia.Controls/Calendar/CalendarButton.cs
@@ -39,7 +39,7 @@ namespace Avalonia.Controls.Primitives
         public CalendarButton()
             : base()
         {
-            Content = DateTimeHelper.GetCurrentDateFormat().AbbreviatedMonthNames[0];
+            SetCurrentValue(ContentProperty, DateTimeHelper.GetCurrentDateFormat().AbbreviatedMonthNames[0]);
         }
 
         /// <summary>
diff --git a/src/Avalonia.Controls/Calendar/CalendarDayButton.cs b/src/Avalonia.Controls/Calendar/CalendarDayButton.cs
index 3d0befdba7..ea3ca8e8fc 100644
--- a/src/Avalonia.Controls/Calendar/CalendarDayButton.cs
+++ b/src/Avalonia.Controls/Calendar/CalendarDayButton.cs
@@ -34,7 +34,7 @@ namespace Avalonia.Controls.Primitives
             : base()
         {
             //Focusable = false;
-            Content = DefaultContent.ToString(CultureInfo.CurrentCulture);
+            SetCurrentValue(ContentProperty, DefaultContent.ToString(CultureInfo.CurrentCulture));
         }
 
         /// <summary>
diff --git a/src/Avalonia.Controls/ComboBox.cs b/src/Avalonia.Controls/ComboBox.cs
index 926cd5d58e..bce1a3685f 100644
--- a/src/Avalonia.Controls/ComboBox.cs
+++ b/src/Avalonia.Controls/ComboBox.cs
@@ -361,19 +361,6 @@ namespace Avalonia.Controls
 
             _subscriptionsOnOpen.Clear();
 
-            var toplevel = TopLevel.GetTopLevel(this);
-            if (toplevel != null)
-            {
-                toplevel.AddDisposableHandler(PointerWheelChangedEvent, (s, ev) =>
-                {
-                    //eat wheel scroll event outside dropdown popup while it's open
-                    if (IsDropDownOpen && (ev.Source as Visual)?.GetVisualRoot() == toplevel)
-                    {
-                        ev.Handled = true;
-                    }
-                }, Interactivity.RoutingStrategies.Tunnel).DisposeWith(_subscriptionsOnOpen);
-            }
-
             this.GetObservable(IsVisibleProperty).Subscribe(IsVisibleChanged).DisposeWith(_subscriptionsOnOpen);
 
             foreach (var parent in this.GetVisualAncestors().OfType<Control>())
diff --git a/src/Avalonia.Controls/ContentControl.cs b/src/Avalonia.Controls/ContentControl.cs
index 0362f7ade4..867dca2be1 100644
--- a/src/Avalonia.Controls/ContentControl.cs
+++ b/src/Avalonia.Controls/ContentControl.cs
@@ -13,7 +13,7 @@ namespace Avalonia.Controls
     /// <summary>
     /// Displays <see cref="Content"/> according to an <see cref="IDataTemplate"/>.
     /// </summary>
-    [TemplatePart("PART_ContentPresenter", typeof(IContentPresenter))]
+    [TemplatePart("PART_ContentPresenter", typeof(ContentPresenter))]
     public class ContentControl : TemplatedControl, IContentControl, IContentPresenterHost
     {
         /// <summary>
@@ -68,7 +68,7 @@ namespace Avalonia.Controls
         /// <summary>
         /// Gets the presenter from the control's template.
         /// </summary>
-        public IContentPresenter? Presenter
+        public ContentPresenter? Presenter
         {
             get;
             private set;
@@ -96,16 +96,16 @@ namespace Avalonia.Controls
         IAvaloniaList<ILogical> IContentPresenterHost.LogicalChildren => LogicalChildren;
 
         /// <inheritdoc/>
-        bool IContentPresenterHost.RegisterContentPresenter(IContentPresenter presenter)
+        bool IContentPresenterHost.RegisterContentPresenter(ContentPresenter presenter)
         {
             return RegisterContentPresenter(presenter);
         }
 
         /// <summary>
-        /// Called when an <see cref="IContentPresenter"/> is registered with the control.
+        /// Called when an <see cref="ContentPresenter"/> is registered with the control.
         /// </summary>
         /// <param name="presenter">The presenter.</param>
-        protected virtual bool RegisterContentPresenter(IContentPresenter presenter)
+        protected virtual bool RegisterContentPresenter(ContentPresenter presenter)
         {
             if (presenter.Name == "PART_ContentPresenter")
             {
diff --git a/src/Avalonia.Controls/ContextMenu.cs b/src/Avalonia.Controls/ContextMenu.cs
index a9d8e4c9c7..3dc1514667 100644
--- a/src/Avalonia.Controls/ContextMenu.cs
+++ b/src/Avalonia.Controls/ContextMenu.cs
@@ -196,14 +196,14 @@ namespace Avalonia.Controls
         /// <see cref="P:Avalonia.Controls.ContextMenu.IsOpen" />
         /// property is changing from false to true.
         /// </summary>
-        public event CancelEventHandler? ContextMenuOpening;
+        public event CancelEventHandler? Opening;
 
         /// <summary>
         /// Occurs when the value of the
         /// <see cref="P:Avalonia.Controls.ContextMenu.IsOpen" />
         /// property is changing from true to false.
         /// </summary>
-        public event CancelEventHandler? ContextMenuClosing;
+        public event CancelEventHandler? Closing;
 
         /// <summary>
         /// Called when the <see cref="Control.ContextMenu"/> property changes on a control.
@@ -353,7 +353,7 @@ namespace Avalonia.Controls
 
             RaiseEvent(new RoutedEventArgs
             {
-                RoutedEvent = MenuOpenedEvent,
+                RoutedEvent = OpenedEvent,
                 Source = this,
             });
         }
@@ -394,7 +394,7 @@ namespace Avalonia.Controls
 
             RaiseEvent(new RoutedEventArgs
             {
-                RoutedEvent = MenuClosedEvent,
+                RoutedEvent = ClosedEvent,
                 Source = this,
             });
             
@@ -446,14 +446,14 @@ namespace Avalonia.Controls
         private bool CancelClosing()
         {
             var eventArgs = new CancelEventArgs();
-            ContextMenuClosing?.Invoke(this, eventArgs);
+            Closing?.Invoke(this, eventArgs);
             return eventArgs.Cancel;
         }
 
         private bool CancelOpening()
         {
             var eventArgs = new CancelEventArgs();
-            ContextMenuOpening?.Invoke(this, eventArgs);
+            Opening?.Invoke(this, eventArgs);
             return eventArgs.Cancel;
         }
     }
diff --git a/src/Avalonia.Controls/Control.cs b/src/Avalonia.Controls/Control.cs
index 13e3978ca6..8d140bdd62 100644
--- a/src/Avalonia.Controls/Control.cs
+++ b/src/Avalonia.Controls/Control.cs
@@ -440,6 +440,12 @@ namespace Avalonia.Controls
             return new NoneAutomationPeer(this);
         }
 
+        internal AutomationPeer? GetAutomationPeer()
+        {
+            VerifyAccess();
+            return _automationPeer;
+        }
+
         internal AutomationPeer GetOrCreateAutomationPeer()
         {
             VerifyAccess();
diff --git a/src/Avalonia.Controls/DateTimePickers/DatePickerPresenter.cs b/src/Avalonia.Controls/DateTimePickers/DatePickerPresenter.cs
index fb61ea679c..8ff8088a34 100644
--- a/src/Avalonia.Controls/DateTimePickers/DatePickerPresenter.cs
+++ b/src/Avalonia.Controls/DateTimePickers/DatePickerPresenter.cs
@@ -367,11 +367,11 @@ namespace Avalonia.Controls
             var dt = Date;
             if (DayVisible)
             {
+                _daySelector.FormatDate = dt.Date;
                 var maxDays = _calendar.GetDaysInMonth(dt.Year, dt.Month);
                 _daySelector.MaximumValue = maxDays;
                 _daySelector.MinimumValue = 1;
                 _daySelector.SelectedValue = dt.Day;
-                _daySelector.FormatDate = dt.Date;
             }
 
             if (MonthVisible)
diff --git a/src/Avalonia.Controls/Embedding/EmbeddableControlRoot.cs b/src/Avalonia.Controls/Embedding/EmbeddableControlRoot.cs
index 7a0ab36050..880bbb7340 100644
--- a/src/Avalonia.Controls/Embedding/EmbeddableControlRoot.cs
+++ b/src/Avalonia.Controls/Embedding/EmbeddableControlRoot.cs
@@ -26,6 +26,10 @@ namespace Avalonia.Controls.Embedding
             LayoutManager.ExecuteInitialLayoutPass();
         }
 
+        public new void StartRendering() => base.StartRendering();
+
+        public new void StopRendering() => base.StopRendering();
+        
         private void EnsureInitialized()
         {
             if (!this.IsInitialized)
diff --git a/src/Avalonia.Controls/Embedding/Offscreen/OffscreenTopLevelImpl.cs b/src/Avalonia.Controls/Embedding/Offscreen/OffscreenTopLevelImpl.cs
index 387357dddd..f379120638 100644
--- a/src/Avalonia.Controls/Embedding/Offscreen/OffscreenTopLevelImpl.cs
+++ b/src/Avalonia.Controls/Embedding/Offscreen/OffscreenTopLevelImpl.cs
@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Diagnostics;
 using Avalonia.Input;
 using Avalonia.Input.Raw;
+using Avalonia.Media;
 using Avalonia.Metadata;
 using Avalonia.Platform;
 using Avalonia.Rendering;
@@ -34,10 +35,13 @@ namespace Avalonia.Controls.Embedding.Offscreen
             public void TriggerTick() => Tick?.Invoke(St.Elapsed);
         }
 
+        public Compositor Compositor { get; }
 
-        public IRenderer CreateRenderer(IRenderRoot root) =>
-            new CompositingRenderer(root, new Compositor(new RenderLoop(_manualRenderTimer, Dispatcher.UIThread), null),
-                () => Surfaces);
+        public OffscreenTopLevelImplBase()
+        {
+            Compositor = new Compositor(new RenderLoop(_manualRenderTimer), null, false,
+                MediaContext.Instance, false);
+        }
 
         public abstract IEnumerable<object> Surfaces { get; }
 
@@ -89,9 +93,9 @@ namespace Avalonia.Controls.Embedding.Offscreen
         public Action? LostFocus { get; set; }
         public abstract IMouseDevice MouseDevice { get; }
 
-        public void SetTransparencyLevelHint(WindowTransparencyLevel transparencyLevel) { }
+        public void SetTransparencyLevelHint(IReadOnlyList<WindowTransparencyLevel> transparencyLevel) { }
 
-        public WindowTransparencyLevel TransparencyLevel { get; private set; }
+        public WindowTransparencyLevel TransparencyLevel => WindowTransparencyLevel.None;
 
         public IPopupImpl? CreatePopup() => null;
         
diff --git a/src/Avalonia.Controls/ExperimentalAcrylicBorder.cs b/src/Avalonia.Controls/ExperimentalAcrylicBorder.cs
index bc17fe7237..be1a90258c 100644
--- a/src/Avalonia.Controls/ExperimentalAcrylicBorder.cs
+++ b/src/Avalonia.Controls/ExperimentalAcrylicBorder.cs
@@ -56,22 +56,12 @@ namespace Avalonia.Controls
                 {
                     if (tl.PlatformImpl is null)
                         return;
-
-                    switch (x)
-                    {
-                        case WindowTransparencyLevel.Transparent:
-                        case WindowTransparencyLevel.None:
-                            Material.PlatformTransparencyCompensationLevel = tl.PlatformImpl.AcrylicCompensationLevels.TransparentLevel;
-                            break;
-
-                        case WindowTransparencyLevel.Blur:
-                            Material.PlatformTransparencyCompensationLevel = tl.PlatformImpl.AcrylicCompensationLevels.BlurLevel;
-                            break;
-
-                        case WindowTransparencyLevel.AcrylicBlur:
-                            Material.PlatformTransparencyCompensationLevel = tl.PlatformImpl.AcrylicCompensationLevels.AcrylicBlurLevel;
-                            break;
-                    }
+                    if (x == WindowTransparencyLevel.Transparent || x == WindowTransparencyLevel.None)
+                        Material.PlatformTransparencyCompensationLevel = tl.PlatformImpl.AcrylicCompensationLevels.TransparentLevel;
+                    else if (x == WindowTransparencyLevel.Blur)
+                        Material.PlatformTransparencyCompensationLevel = tl.PlatformImpl.AcrylicCompensationLevels.BlurLevel;
+                    else if (x == WindowTransparencyLevel.AcrylicBlur)
+                        Material.PlatformTransparencyCompensationLevel = tl.PlatformImpl.AcrylicCompensationLevels.AcrylicBlurLevel;
                 });
             UpdateMaterialSubscription();
         }
diff --git a/src/Avalonia.Controls/GridSplitter.cs b/src/Avalonia.Controls/GridSplitter.cs
index 4684304725..234c1ff27a 100644
--- a/src/Avalonia.Controls/GridSplitter.cs
+++ b/src/Avalonia.Controls/GridSplitter.cs
@@ -695,7 +695,8 @@ namespace Avalonia.Controls
         {
             private readonly TranslateTransform _translation;
             private readonly Decorator _decorator;
-            
+
+            [System.Diagnostics.CodeAnalysis.SuppressMessage("AvaloniaProperty", "AVP1012", Justification = "Private object")]
             public PreviewAdorner(Control? previewControl)
             {
                 // Add a decorator to perform translations.
diff --git a/src/Avalonia.Controls/Menu.cs b/src/Avalonia.Controls/Menu.cs
index fe4d42c603..6a8cf2b515 100644
--- a/src/Avalonia.Controls/Menu.cs
+++ b/src/Avalonia.Controls/Menu.cs
@@ -60,7 +60,7 @@ namespace Avalonia.Controls
 
             RaiseEvent(new RoutedEventArgs
             {
-                RoutedEvent = MenuClosedEvent,
+                RoutedEvent = ClosedEvent,
                 Source = this,
             });
         }
@@ -77,7 +77,7 @@ namespace Avalonia.Controls
 
             RaiseEvent(new RoutedEventArgs
             {
-                RoutedEvent = MenuOpenedEvent,
+                RoutedEvent = OpenedEvent,
                 Source = this,
             });
         }
diff --git a/src/Avalonia.Controls/MenuBase.cs b/src/Avalonia.Controls/MenuBase.cs
index 7fc804a338..e57fadffee 100644
--- a/src/Avalonia.Controls/MenuBase.cs
+++ b/src/Avalonia.Controls/MenuBase.cs
@@ -25,16 +25,16 @@ namespace Avalonia.Controls
                 o => o.IsOpen);
 
         /// <summary>
-        /// Defines the <see cref="MenuOpened"/> event.
+        /// Defines the <see cref="Opened"/> event.
         /// </summary>
-        public static readonly RoutedEvent<RoutedEventArgs> MenuOpenedEvent =
-            RoutedEvent.Register<MenuBase, RoutedEventArgs>(nameof(MenuOpened), RoutingStrategies.Bubble);
+        public static readonly RoutedEvent<RoutedEventArgs> OpenedEvent =
+            RoutedEvent.Register<MenuBase, RoutedEventArgs>(nameof(Opened), RoutingStrategies.Bubble);
 
         /// <summary>
-        /// Defines the <see cref="MenuClosed"/> event.
+        /// Defines the <see cref="Closed"/> event.
         /// </summary>
-        public static readonly RoutedEvent<RoutedEventArgs> MenuClosedEvent =
-            RoutedEvent.Register<MenuBase, RoutedEventArgs>(nameof(MenuClosed), RoutingStrategies.Bubble);
+        public static readonly RoutedEvent<RoutedEventArgs> ClosedEvent =
+            RoutedEvent.Register<MenuBase, RoutedEventArgs>(nameof(Closed), RoutingStrategies.Bubble);
 
         private bool _isOpen;
 
@@ -68,8 +68,8 @@ namespace Avalonia.Controls
         /// </summary>
         public bool IsOpen
         {
-            get { return _isOpen; }
-            protected set { SetAndRaise(IsOpenProperty, ref _isOpen, value); }
+            get => _isOpen;
+            protected set => SetAndRaise(IsOpenProperty, ref _isOpen, value);
         }
 
         /// <inheritdoc/>
@@ -105,19 +105,19 @@ namespace Avalonia.Controls
         /// <summary>
         /// Occurs when a <see cref="Menu"/> is opened.
         /// </summary>
-        public event EventHandler<RoutedEventArgs>? MenuOpened
+        public event EventHandler<RoutedEventArgs>? Opened
         {
-            add { AddHandler(MenuOpenedEvent, value); }
-            remove { RemoveHandler(MenuOpenedEvent, value); }
+            add => AddHandler(OpenedEvent, value);
+            remove => RemoveHandler(OpenedEvent, value);
         }
 
         /// <summary>
         /// Occurs when a <see cref="Menu"/> is closed.
         /// </summary>
-        public event EventHandler<RoutedEventArgs>? MenuClosed
+        public event EventHandler<RoutedEventArgs>? Closed
         {
-            add { AddHandler(MenuClosedEvent, value); }
-            remove { RemoveHandler(MenuClosedEvent, value); }
+            add => AddHandler(ClosedEvent, value);
+            remove => RemoveHandler(ClosedEvent, value);
         }
 
         /// <summary>
diff --git a/src/Avalonia.Controls/NativeControlHost.cs b/src/Avalonia.Controls/NativeControlHost.cs
index aa3d6db9e0..67e4c5cf48 100644
--- a/src/Avalonia.Controls/NativeControlHost.cs
+++ b/src/Avalonia.Controls/NativeControlHost.cs
@@ -129,7 +129,7 @@ namespace Avalonia.Controls
             if(_queuedForMoveResize)
                 return;
             _queuedForMoveResize = true;
-            Dispatcher.UIThread.Post(UpdateHost, DispatcherPriority.Render);
+            Dispatcher.UIThread.Post(UpdateHost, DispatcherPriority.AfterRender);
         }
 
         public bool TryUpdateNativeControlPosition()
diff --git a/src/Avalonia.Controls/NativeMenuItemSeparator.cs b/src/Avalonia.Controls/NativeMenuItemSeparator.cs
index f55d714884..55b3fd08de 100644
--- a/src/Avalonia.Controls/NativeMenuItemSeparator.cs
+++ b/src/Avalonia.Controls/NativeMenuItemSeparator.cs
@@ -4,7 +4,7 @@
     {
         public NativeMenuItemSeparator()
         {
-            Header = "-";
+            SetCurrentValue(HeaderProperty, "-");
         }
     }
 }
diff --git a/src/Avalonia.Controls/Platform/DefaultMenuInteractionHandler.cs b/src/Avalonia.Controls/Platform/DefaultMenuInteractionHandler.cs
index 79a3038edf..6a76855d85 100644
--- a/src/Avalonia.Controls/Platform/DefaultMenuInteractionHandler.cs
+++ b/src/Avalonia.Controls/Platform/DefaultMenuInteractionHandler.cs
@@ -290,7 +290,7 @@ namespace Avalonia.Controls.Platform
             Menu.PointerPressed += PointerPressed;
             Menu.PointerReleased += PointerReleased;
             Menu.AddHandler(AccessKeyHandler.AccessKeyPressedEvent, AccessKeyPressed);
-            Menu.AddHandler(MenuBase.MenuOpenedEvent, MenuOpened);
+            Menu.AddHandler(MenuBase.OpenedEvent, MenuOpened);
             Menu.AddHandler(MenuItem.PointerEnteredItemEvent, PointerEntered);
             Menu.AddHandler(MenuItem.PointerExitedItemEvent, PointerExited);
             Menu.AddHandler(InputElement.PointerMovedEvent, PointerMoved);
@@ -326,7 +326,7 @@ namespace Avalonia.Controls.Platform
             Menu.PointerPressed -= PointerPressed;
             Menu.PointerReleased -= PointerReleased;
             Menu.RemoveHandler(AccessKeyHandler.AccessKeyPressedEvent, AccessKeyPressed);
-            Menu.RemoveHandler(MenuBase.MenuOpenedEvent, MenuOpened);
+            Menu.RemoveHandler(MenuBase.OpenedEvent, MenuOpened);
             Menu.RemoveHandler(MenuItem.PointerEnteredItemEvent, PointerEntered);
             Menu.RemoveHandler(MenuItem.PointerExitedItemEvent, PointerExited);
             Menu.RemoveHandler(InputElement.PointerMovedEvent, PointerMoved);
diff --git a/src/Avalonia.Controls/Platform/INativeApplicationCommands.cs b/src/Avalonia.Controls/Platform/INativeApplicationCommands.cs
index 6720b8aa2c..d837e4155e 100644
--- a/src/Avalonia.Controls/Platform/INativeApplicationCommands.cs
+++ b/src/Avalonia.Controls/Platform/INativeApplicationCommands.cs
@@ -3,7 +3,7 @@ namespace Avalonia.Controls.Platform
     /// <summary>
     /// Native Menu Default Application Commands
     /// </summary>
-    public interface INativeApplicationCommands
+    internal interface INativeApplicationCommands
     {
         void HideApp();
         void ShowAll();
diff --git a/src/Avalonia.Controls/Platform/IPlatformNativeSurfaceHandle.cs b/src/Avalonia.Controls/Platform/IPlatformNativeSurfaceHandle.cs
index 6ad07b1b13..068ee39e84 100644
--- a/src/Avalonia.Controls/Platform/IPlatformNativeSurfaceHandle.cs
+++ b/src/Avalonia.Controls/Platform/IPlatformNativeSurfaceHandle.cs
@@ -4,7 +4,7 @@ using Avalonia.Metadata;
 namespace Avalonia.Platform
 {
     [Unstable]
-    public interface IPlatformNativeSurfaceHandle : IPlatformHandle
+    public interface INativePlatformHandleSurface : IPlatformHandle
     {
         PixelSize Size { get; }
         double Scaling { get; }
diff --git a/src/Avalonia.Controls/Platform/ITopLevelImpl.cs b/src/Avalonia.Controls/Platform/ITopLevelImpl.cs
index bb6b2304af..35478053c4 100644
--- a/src/Avalonia.Controls/Platform/ITopLevelImpl.cs
+++ b/src/Avalonia.Controls/Platform/ITopLevelImpl.cs
@@ -6,6 +6,7 @@ using Avalonia.Input.Raw;
 using Avalonia.Layout;
 using Avalonia.Metadata;
 using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
 
 namespace Avalonia.Platform
 {
@@ -72,10 +73,9 @@ namespace Avalonia.Platform
         Action<WindowTransparencyLevel>? TransparencyLevelChanged { get; set; }
 
         /// <summary>
-        /// Creates a new renderer for the toplevel.
+        /// Gets the compositor that's compatible with the toplevel
         /// </summary>
-        /// <param name="root">The toplevel.</param>
-        IRenderer CreateRenderer(IRenderRoot root);
+        Compositor Compositor { get; }
 
         /// <summary>
         /// Sets the <see cref="IInputRoot"/> for the toplevel.
@@ -117,7 +117,7 @@ namespace Avalonia.Platform
         /// <summary>
         /// Sets the <see cref="WindowTransparencyLevel"/> hint of the TopLevel.
         /// </summary>
-        void SetTransparencyLevelHint(WindowTransparencyLevel transparencyLevel);
+        void SetTransparencyLevelHint(IReadOnlyList<WindowTransparencyLevel> transparencyLevels);
 
         /// <summary>
         /// Gets the current <see cref="WindowTransparencyLevel"/> of the TopLevel.
diff --git a/src/Avalonia.Controls/Presenters/ContentPresenter.cs b/src/Avalonia.Controls/Presenters/ContentPresenter.cs
index 972fd2d4ff..7a81454bb0 100644
--- a/src/Avalonia.Controls/Presenters/ContentPresenter.cs
+++ b/src/Avalonia.Controls/Presenters/ContentPresenter.cs
@@ -17,7 +17,7 @@ namespace Avalonia.Controls.Presenters
     /// Presents a single item of data inside a <see cref="TemplatedControl"/> template.
     /// </summary>
     [PseudoClasses(":empty")]
-    public class ContentPresenter : Control, IContentPresenter
+    public class ContentPresenter : Control
     {
         /// <summary>
         /// Defines the <see cref="Background"/> property.
diff --git a/src/Avalonia.Controls/Presenters/IContentPresenter.cs b/src/Avalonia.Controls/Presenters/IContentPresenter.cs
deleted file mode 100644
index 01aec3855f..0000000000
--- a/src/Avalonia.Controls/Presenters/IContentPresenter.cs
+++ /dev/null
@@ -1,23 +0,0 @@
-using Avalonia.Controls.Primitives;
-using Avalonia.Metadata;
-
-namespace Avalonia.Controls.Presenters
-{
-    /// <summary>
-    /// Interface for controls that present a single item of data inside a
-    /// <see cref="TemplatedControl"/> template.
-    /// </summary>
-    [NotClientImplementable]
-    public interface IContentPresenter : IPresenter
-    {
-        /// <summary>
-        /// Gets the control displayed by the presenter.
-        /// </summary>
-        Control? Child { get; }
-
-        /// <summary>
-        /// Gets or sets the content to be displayed by the presenter.
-        /// </summary>
-        object? Content { get; set; }
-    }
-}
diff --git a/src/Avalonia.Controls/Presenters/IContentPresenterHost.cs b/src/Avalonia.Controls/Presenters/IContentPresenterHost.cs
index dd1aafba65..6b1c733f37 100644
--- a/src/Avalonia.Controls/Presenters/IContentPresenterHost.cs
+++ b/src/Avalonia.Controls/Presenters/IContentPresenterHost.cs
@@ -22,13 +22,13 @@ namespace Avalonia.Controls.Presenters
         IAvaloniaList<ILogical> LogicalChildren { get; }
 
         /// <summary>
-        /// Registers an <see cref="IContentPresenter"/> with a host control.
+        /// Registers an <see cref="ContentPresenter"/> with a host control.
         /// </summary>
         /// <param name="presenter">The content presenter.</param>
         /// <returns>
         /// True if the content presenter should add its child to the logical children of the
         /// host; otherwise false.
         /// </returns>
-        bool RegisterContentPresenter(IContentPresenter presenter);
+        bool RegisterContentPresenter(ContentPresenter presenter);
     }
 }
diff --git a/src/Avalonia.Controls/Presenters/IPresenter.cs b/src/Avalonia.Controls/Presenters/IPresenter.cs
deleted file mode 100644
index dc1d40cdcd..0000000000
--- a/src/Avalonia.Controls/Presenters/IPresenter.cs
+++ /dev/null
@@ -1,20 +0,0 @@
-using Avalonia.Controls.Primitives;
-using Avalonia.Metadata;
-
-namespace Avalonia.Controls.Presenters
-{
-    /// <summary>
-    /// Interface for presenters such as <see cref="ContentPresenter"/> and
-    /// <see cref="ItemsPresenter"/>.
-    /// </summary>
-    /// <remarks>
-    /// A presenter is the gateway between a templated control and its content. When
-    /// a control which implements <see cref="IPresenter"/> is found in the template
-    /// of a <see cref="TemplatedControl"/> then that signals that the visual child
-    /// of the presenter is not a part of the template.
-    /// </remarks>
-    [NotClientImplementable]
-    public interface IPresenter : INamed
-    {
-    }
-}
diff --git a/src/Avalonia.Controls/Presenters/ScrollContentPresenter.cs b/src/Avalonia.Controls/Presenters/ScrollContentPresenter.cs
index 3ee50ab547..1c9dd79b13 100644
--- a/src/Avalonia.Controls/Presenters/ScrollContentPresenter.cs
+++ b/src/Avalonia.Controls/Presenters/ScrollContentPresenter.cs
@@ -13,7 +13,7 @@ namespace Avalonia.Controls.Presenters
     /// <summary>
     /// Presents a scrolling view of content inside a <see cref="ScrollViewer"/>.
     /// </summary>
-    public class ScrollContentPresenter : ContentPresenter, IPresenter, IScrollable, IScrollAnchorProvider
+    public class ScrollContentPresenter : ContentPresenter, IScrollable, IScrollAnchorProvider
     {
         private const double EdgeDetectionTolerance = 0.1;
 
diff --git a/src/Avalonia.Controls/Presenters/TextPresenter.cs b/src/Avalonia.Controls/Presenters/TextPresenter.cs
index 6fb05463c0..c5b4834ded 100644
--- a/src/Avalonia.Controls/Presenters/TextPresenter.cs
+++ b/src/Avalonia.Controls/Presenters/TextPresenter.cs
@@ -478,7 +478,7 @@ namespace Avalonia.Controls.Presenters
                     {
                         this.BringIntoView(_caretBounds);
                     },
-                    DispatcherPriority.Render);
+                    DispatcherPriority.AfterRender);
             }
         }
 
diff --git a/src/Avalonia.Controls/Primitives/HeaderedContentControl.cs b/src/Avalonia.Controls/Primitives/HeaderedContentControl.cs
index d44ef5666c..d989550222 100644
--- a/src/Avalonia.Controls/Primitives/HeaderedContentControl.cs
+++ b/src/Avalonia.Controls/Primitives/HeaderedContentControl.cs
@@ -41,7 +41,7 @@ namespace Avalonia.Controls.Primitives
         /// <summary>
         /// Gets the header presenter from the control's template.
         /// </summary>
-        public IContentPresenter? HeaderPresenter
+        public ContentPresenter? HeaderPresenter
         {
             get;
             private set;
@@ -57,7 +57,7 @@ namespace Avalonia.Controls.Primitives
         }
 
         /// <inheritdoc/>
-        protected override bool RegisterContentPresenter(IContentPresenter presenter)
+        protected override bool RegisterContentPresenter(ContentPresenter presenter)
         {
             var result = base.RegisterContentPresenter(presenter);
 
diff --git a/src/Avalonia.Controls/Primitives/HeaderedItemsControl.cs b/src/Avalonia.Controls/Primitives/HeaderedItemsControl.cs
index d71439ece6..2236dc8fe4 100644
--- a/src/Avalonia.Controls/Primitives/HeaderedItemsControl.cs
+++ b/src/Avalonia.Controls/Primitives/HeaderedItemsControl.cs
@@ -56,7 +56,7 @@ namespace Avalonia.Controls.Primitives
         /// <summary>
         /// Gets the header presenter from the control's template.
         /// </summary>
-        public IContentPresenter? HeaderPresenter
+        public ContentPresenter? HeaderPresenter
         {
             get;
             private set;
@@ -77,16 +77,16 @@ namespace Avalonia.Controls.Primitives
         }
 
         /// <inheritdoc/>
-        bool IContentPresenterHost.RegisterContentPresenter(IContentPresenter presenter)
+        bool IContentPresenterHost.RegisterContentPresenter(ContentPresenter presenter)
         {
             return RegisterContentPresenter(presenter);
         }
 
         /// <summary>
-        /// Called when an <see cref="IContentPresenter"/> is registered with the control.
+        /// Called when an <see cref="ContentPresenter"/> is registered with the control.
         /// </summary>
         /// <param name="presenter">The presenter.</param>
-        protected virtual bool RegisterContentPresenter(IContentPresenter presenter)
+        protected virtual bool RegisterContentPresenter(ContentPresenter presenter)
         {
             if (presenter.Name == "PART_HeaderPresenter")
             {
diff --git a/src/Avalonia.Controls/Primitives/HeaderedSelectingItemsControl.cs b/src/Avalonia.Controls/Primitives/HeaderedSelectingItemsControl.cs
index 88ca1f1fe1..c0075cb389 100644
--- a/src/Avalonia.Controls/Primitives/HeaderedSelectingItemsControl.cs
+++ b/src/Avalonia.Controls/Primitives/HeaderedSelectingItemsControl.cs
@@ -56,7 +56,7 @@ namespace Avalonia.Controls.Primitives
         /// <summary>
         /// Gets the header presenter from the control's template.
         /// </summary>
-        public IContentPresenter? HeaderPresenter
+        public ContentPresenter? HeaderPresenter
         {
             get;
             private set;
@@ -66,7 +66,7 @@ namespace Avalonia.Controls.Primitives
         IAvaloniaList<ILogical> IContentPresenterHost.LogicalChildren => LogicalChildren;
 
         /// <inheritdoc/>
-        bool IContentPresenterHost.RegisterContentPresenter(IContentPresenter presenter)
+        bool IContentPresenterHost.RegisterContentPresenter(ContentPresenter presenter)
         {
             return RegisterContentPresenter(presenter);
         }
@@ -83,10 +83,10 @@ namespace Avalonia.Controls.Primitives
         }
 
         /// <summary>
-        /// Called when an <see cref="IContentPresenter"/> is registered with the control.
+        /// Called when an <see cref="ContentPresenter"/> is registered with the control.
         /// </summary>
         /// <param name="presenter">The presenter.</param>
-        protected virtual bool RegisterContentPresenter(IContentPresenter presenter)
+        protected virtual bool RegisterContentPresenter(ContentPresenter presenter)
         {
             if (presenter.Name == "PART_HeaderPresenter")
             {
diff --git a/src/Avalonia.Controls/Primitives/IPopupHost.cs b/src/Avalonia.Controls/Primitives/IPopupHost.cs
index 90fbdcdbec..0aad838b0f 100644
--- a/src/Avalonia.Controls/Primitives/IPopupHost.cs
+++ b/src/Avalonia.Controls/Primitives/IPopupHost.cs
@@ -52,7 +52,7 @@ namespace Avalonia.Controls.Primitives
         /// <summary>
         /// Gets the presenter from the control's template.
         /// </summary>
-        IContentPresenter? Presenter { get; }
+        ContentPresenter? Presenter { get; }
 
         /// <summary>
         /// Gets or sets whether the popup appears on top of all other windows.
diff --git a/src/Avalonia.Controls/Primitives/LightDismissOverlayLayer.cs b/src/Avalonia.Controls/Primitives/LightDismissOverlayLayer.cs
index 8525f025a3..94ee99b019 100644
--- a/src/Avalonia.Controls/Primitives/LightDismissOverlayLayer.cs
+++ b/src/Avalonia.Controls/Primitives/LightDismissOverlayLayer.cs
@@ -46,13 +46,12 @@ namespace Avalonia.Controls.Primitives
             return manager?.LightDismissOverlayLayer;
         }
 
+        /// <inheritdoc />
         public bool HitTest(Point point)
         {
             if (InputPassThroughElement is Visual v)
             {
-                var hit = ((Visual?)VisualRoot)?.GetVisualAt(point, x => x != this);
-
-                if (hit is object)
+                if (VisualRoot is IInputElement ie && ie.InputHitTest(point, x => x != this) is Visual hit)
                 {
                     return !v.IsVisualAncestorOf(hit);
                 }
diff --git a/src/Avalonia.Controls/Primitives/OverlayPopupHost.cs b/src/Avalonia.Controls/Primitives/OverlayPopupHost.cs
index 99fd4cd1dc..2236d87dd1 100644
--- a/src/Avalonia.Controls/Primitives/OverlayPopupHost.cs
+++ b/src/Avalonia.Controls/Primitives/OverlayPopupHost.cs
@@ -29,6 +29,7 @@ namespace Avalonia.Controls.Primitives
         }
 
         /// <inheritdoc />
+        [System.Diagnostics.CodeAnalysis.SuppressMessage("AvaloniaProperty", "AVP1012", Justification = "Explicit set")]
         public void SetChild(Control? control)
         {
             Content = control;
@@ -123,7 +124,7 @@ namespace Avalonia.Controls.Primitives
             {
                 OverlayLayer.SetLeft(this, _lastRequestedPosition.X);
                 OverlayLayer.SetTop(this, _lastRequestedPosition.Y);
-            }, DispatcherPriority.Layout);
+            }, DispatcherPriority.Render);
         }
 
         double IManagedPopupPositionerPopup.Scaling => 1;
diff --git a/src/Avalonia.Controls/Primitives/PopupPositioning/ManagedPopupPositioner.cs b/src/Avalonia.Controls/Primitives/PopupPositioning/ManagedPopupPositioner.cs
index 9a60725c7e..f1a5159069 100644
--- a/src/Avalonia.Controls/Primitives/PopupPositioning/ManagedPopupPositioner.cs
+++ b/src/Avalonia.Controls/Primitives/PopupPositioning/ManagedPopupPositioner.cs
@@ -2,9 +2,11 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Transactions;
+using Avalonia.Metadata;
 
 namespace Avalonia.Controls.Primitives.PopupPositioning
 {
+    [PrivateApi]
     public interface IManagedPopupPositionerPopup
     {
         IReadOnlyList<ManagedPopupPositionerScreenInfo> Screens { get; }
@@ -13,6 +15,7 @@ namespace Avalonia.Controls.Primitives.PopupPositioning
         void MoveAndResize(Point devicePoint, Size virtualSize);
     }
 
+    [PrivateApi]
     public class ManagedPopupPositionerScreenInfo
     {
         public Rect Bounds { get; }
@@ -29,6 +32,7 @@ namespace Avalonia.Controls.Primitives.PopupPositioning
     /// An <see cref="IPopupPositioner"/> implementation for platforms on which a popup can be
     /// arbitrarily positioned.
     /// </summary>
+    [PrivateApi]
     public class ManagedPopupPositioner : IPopupPositioner
     {
         private readonly IManagedPopupPositionerPopup _popup;
diff --git a/src/Avalonia.Controls/Primitives/PopupPositioning/ManagedPopupPositionerPopupImplHelper.cs b/src/Avalonia.Controls/Primitives/PopupPositioning/ManagedPopupPositionerPopupImplHelper.cs
index 51a21323d9..41a2a98fd3 100644
--- a/src/Avalonia.Controls/Primitives/PopupPositioning/ManagedPopupPositionerPopupImplHelper.cs
+++ b/src/Avalonia.Controls/Primitives/PopupPositioning/ManagedPopupPositionerPopupImplHelper.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using Avalonia.Metadata;
 using Avalonia.Platform;
 
 namespace Avalonia.Controls.Primitives.PopupPositioning
@@ -8,6 +9,7 @@ namespace Avalonia.Controls.Primitives.PopupPositioning
     /// <summary>
     /// This class is used to simplify integration of IPopupImpl implementations with popup positioner
     /// </summary>
+    [PrivateApi]
     public class ManagedPopupPositionerPopupImplHelper : IManagedPopupPositionerPopup 
     {
         private readonly IWindowBaseImpl _parent;
diff --git a/src/Avalonia.Controls/Primitives/RangeBase.cs b/src/Avalonia.Controls/Primitives/RangeBase.cs
index ebf7879412..33ab78b66f 100644
--- a/src/Avalonia.Controls/Primitives/RangeBase.cs
+++ b/src/Avalonia.Controls/Primitives/RangeBase.cs
@@ -45,14 +45,14 @@ namespace Avalonia.Controls.Primitives
         /// <summary>
         /// Defines the <see cref="ValueChanged"/> event.
         /// </summary>
-        public static readonly RoutedEvent<RoutedPropertyChangedEventArgs<double>> ValueChangedEvent =
-            RoutedEvent.Register<RangeBase, RoutedPropertyChangedEventArgs<double>>(
+        public static readonly RoutedEvent<RangeBaseValueChangedEventArgs> ValueChangedEvent =
+            RoutedEvent.Register<RangeBase, RangeBaseValueChangedEventArgs>(
                 nameof(ValueChanged), RoutingStrategies.Bubble);
 
         /// <summary>
         /// Occurs when the <see cref="Value"/> property changes.
         /// </summary>
-        public event EventHandler<RoutedPropertyChangedEventArgs<double>>? ValueChanged
+        public event EventHandler<RangeBaseValueChangedEventArgs>? ValueChanged
         {
             add => AddHandler(ValueChangedEvent, value);
             remove => RemoveHandler(ValueChangedEvent, value);
@@ -163,7 +163,7 @@ namespace Avalonia.Controls.Primitives
             }
             else if (change.Property == ValueProperty)
             {
-                var valueChangedEventArgs = new RoutedPropertyChangedEventArgs<double>(
+                var valueChangedEventArgs = new RangeBaseValueChangedEventArgs(
                     change.GetOldValue<double>(),
                     change.GetNewValue<double>(),
                     ValueChangedEvent);
diff --git a/src/Avalonia.Controls/Primitives/RangeBaseValueChangedEventArgs.cs b/src/Avalonia.Controls/Primitives/RangeBaseValueChangedEventArgs.cs
new file mode 100644
index 0000000000..480e82e4fc
--- /dev/null
+++ b/src/Avalonia.Controls/Primitives/RangeBaseValueChangedEventArgs.cs
@@ -0,0 +1,47 @@
+using Avalonia.Interactivity;
+
+namespace Avalonia.Controls.Primitives
+{
+    /// <summary>
+    /// Provides data specific to a <see cref="RangeBase.ValueChanged"/> event.
+    /// </summary>
+    public class RangeBaseValueChangedEventArgs : RoutedEventArgs
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="RangeBaseValueChangedEventArgs"/> class.
+        /// </summary>
+        /// <param name="oldValue">The old value of the range value property.</param>
+        /// <param name="newValue">The new value of the range value property.</param>
+        /// <param name="routedEvent">The routed event associated with these event args.</param>
+        public RangeBaseValueChangedEventArgs(double oldValue, double newValue, RoutedEvent? routedEvent)
+            : base(routedEvent)
+        {
+            OldValue = oldValue;
+            NewValue = newValue;
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="RangeBaseValueChangedEventArgs"/> class.
+        /// </summary>
+        /// <param name="oldValue">The old value of the range value property.</param>
+        /// <param name="newValue">The new value of the range value property.</param>
+        /// <param name="routedEvent">The routed event associated with these event args.</param>
+        /// <param name="source">The source object that raised the routed event.</param>
+        public RangeBaseValueChangedEventArgs(double oldValue, double newValue, RoutedEvent? routedEvent, object? source)
+            : base(routedEvent, source)
+        {
+            OldValue = oldValue;
+            NewValue = newValue;
+        }
+
+        /// <summary>
+        /// Gets the old value of the range value property.
+        /// </summary>
+        public double OldValue { get; init; }
+
+        /// <summary>
+        /// Gets the new value of the range value property.
+        /// </summary>
+        public double NewValue { get; init; }
+    }
+}
diff --git a/src/Avalonia.Controls/ProgressBar.cs b/src/Avalonia.Controls/ProgressBar.cs
index 7dcdaa2f8d..3dad162286 100644
--- a/src/Avalonia.Controls/ProgressBar.cs
+++ b/src/Avalonia.Controls/ProgressBar.cs
@@ -31,77 +31,157 @@ namespace Avalonia.Controls
             private double _containerAnimationEndPosition;
             private double _container2AnimationStartPosition;
             private double _container2AnimationEndPosition;
-
-            public static readonly DirectProperty<ProgressBarTemplateSettings, double> ContainerAnimationStartPositionProperty =
-           AvaloniaProperty.RegisterDirect<ProgressBarTemplateSettings, double>(
-               nameof(ContainerAnimationStartPosition),
-               p => p.ContainerAnimationStartPosition,
-               (p, o) => p.ContainerAnimationStartPosition = o, 0d);
-
-            public static readonly DirectProperty<ProgressBarTemplateSettings, double> ContainerAnimationEndPositionProperty =
-                AvaloniaProperty.RegisterDirect<ProgressBarTemplateSettings, double>(
-                    nameof(ContainerAnimationEndPosition),
-                    p => p.ContainerAnimationEndPosition,
-                    (p, o) => p.ContainerAnimationEndPosition = o, 0d);
-
-            public static readonly DirectProperty<ProgressBarTemplateSettings, double> Container2AnimationStartPositionProperty =
-                AvaloniaProperty.RegisterDirect<ProgressBarTemplateSettings, double>(
-                    nameof(Container2AnimationStartPosition),
-                    p => p.Container2AnimationStartPosition,
-                    (p, o) => p.Container2AnimationStartPosition = o, 0d);
-
-            public static readonly DirectProperty<ProgressBarTemplateSettings, double> Container2AnimationEndPositionProperty =
-                AvaloniaProperty.RegisterDirect<ProgressBarTemplateSettings, double>(
-                    nameof(Container2AnimationEndPosition),
-                    p => p.Container2AnimationEndPosition,
-                    (p, o) => p.Container2AnimationEndPosition = o);
-
+            private double _indeterminateStartingOffset;
+            private double _indeterminateEndingOffset;
+
+            /// <summary>
+            /// Defines the <see cref="ContainerAnimationStartPosition"/> property.
+            /// </summary>
+            public static readonly DirectProperty<ProgressBarTemplateSettings, double>
+                ContainerAnimationStartPositionProperty =
+                    AvaloniaProperty.RegisterDirect<ProgressBarTemplateSettings, double>(
+                        nameof(ContainerAnimationStartPosition),
+                        p => p.ContainerAnimationStartPosition,
+                        (p, o) => p.ContainerAnimationStartPosition = o);
+
+            /// <summary>
+            /// Defines the <see cref="ContainerAnimationEndPosition"/> property.
+            /// </summary>
+            public static readonly DirectProperty<ProgressBarTemplateSettings, double>
+                ContainerAnimationEndPositionProperty =
+                    AvaloniaProperty.RegisterDirect<ProgressBarTemplateSettings, double>(
+                        nameof(ContainerAnimationEndPosition),
+                        p => p.ContainerAnimationEndPosition,
+                        (p, o) => p.ContainerAnimationEndPosition = o);
+
+            /// <summary>
+            /// Defines the <see cref="Container2AnimationStartPosition"/> property.
+            /// </summary>
+            public static readonly DirectProperty<ProgressBarTemplateSettings, double>
+                Container2AnimationStartPositionProperty =
+                    AvaloniaProperty.RegisterDirect<ProgressBarTemplateSettings, double>(
+                        nameof(Container2AnimationStartPosition),
+                        p => p.Container2AnimationStartPosition,
+                        (p, o) => p.Container2AnimationStartPosition = o);
+
+            /// <summary>
+            /// Defines the <see cref="Container2AnimationEndPosition"/> property.
+            /// </summary>
+            public static readonly DirectProperty<ProgressBarTemplateSettings, double>
+                Container2AnimationEndPositionProperty =
+                    AvaloniaProperty.RegisterDirect<ProgressBarTemplateSettings, double>(
+                        nameof(Container2AnimationEndPosition),
+                        p => p.Container2AnimationEndPosition,
+                        (p, o) => p.Container2AnimationEndPosition = o);
+
+            /// <summary>
+            /// Defines the <see cref="Container2Width"/> property.
+            /// </summary>
             public static readonly DirectProperty<ProgressBarTemplateSettings, double> Container2WidthProperty =
                 AvaloniaProperty.RegisterDirect<ProgressBarTemplateSettings, double>(
                     nameof(Container2Width),
                     p => p.Container2Width,
                     (p, o) => p.Container2Width = o);
 
+            /// <summary>
+            /// Defines the <see cref="ContainerWidth"/> property.
+            /// </summary>
             public static readonly DirectProperty<ProgressBarTemplateSettings, double> ContainerWidthProperty =
                 AvaloniaProperty.RegisterDirect<ProgressBarTemplateSettings, double>(
                     nameof(ContainerWidth),
                     p => p.ContainerWidth,
                     (p, o) => p.ContainerWidth = o);
 
+            /// <summary>
+            /// Defines the <see cref="IndeterminateStartingOffset"/> property.
+            /// </summary>
+            public static readonly DirectProperty<ProgressBarTemplateSettings, double> IndeterminateStartingOffsetProperty =
+                AvaloniaProperty.RegisterDirect<ProgressBarTemplateSettings, double>(
+                    nameof(IndeterminateStartingOffset),
+                    p => p.IndeterminateStartingOffset,
+                    (p, o) => p.IndeterminateStartingOffset = o);
+            
+            /// <summary>
+            /// Defines the <see cref="IndeterminateEndingOffset"/> property.
+            /// </summary>
+            public static readonly DirectProperty<ProgressBarTemplateSettings, double> IndeterminateEndingOffsetProperty =
+                AvaloniaProperty.RegisterDirect<ProgressBarTemplateSettings, double>(
+                    nameof(IndeterminateEndingOffset),
+                    p => p.IndeterminateEndingOffset,
+                    (p, o) => p.IndeterminateEndingOffset = o);
+
+            /// <summary>
+            /// Used by <see cref="Avalonia.Themes.Fluent"/> to define the first indeterminate indicator's width.
+            /// </summary>
+            public double ContainerWidth
+            {
+                get => _containerWidth;
+                set => SetAndRaise(ContainerWidthProperty, ref _containerWidth, value);
+            }
+            
+            /// <summary>
+            /// Used by <see cref="Avalonia.Themes.Fluent"/> to define the second indeterminate indicator's width.
+            /// </summary>
+            public double Container2Width
+            {
+                get => _container2Width;
+                set => SetAndRaise(Container2WidthProperty, ref _container2Width, value);
+            }
+
+            /// <summary>
+            /// Used by <see cref="Avalonia.Themes.Fluent"/> to define the first indeterminate indicator's start position when animated.
+            /// </summary>
             public double ContainerAnimationStartPosition
             {
                 get => _containerAnimationStartPosition;
-                set => SetAndRaise(ContainerAnimationStartPositionProperty, ref _containerAnimationStartPosition, value);
+                set => SetAndRaise(ContainerAnimationStartPositionProperty, ref _containerAnimationStartPosition,
+                    value);
             }
 
+            /// <summary>
+            /// Used by <see cref="Avalonia.Themes.Fluent"/> to define the first indeterminate indicator's end position when animated.
+            /// </summary>
             public double ContainerAnimationEndPosition
             {
                 get => _containerAnimationEndPosition;
                 set => SetAndRaise(ContainerAnimationEndPositionProperty, ref _containerAnimationEndPosition, value);
             }
 
+            /// <summary>
+            /// Used by <see cref="Avalonia.Themes.Fluent"/> to define the second indeterminate indicator's start position when animated.
+            /// </summary>
             public double Container2AnimationStartPosition
             {
                 get => _container2AnimationStartPosition;
-                set => SetAndRaise(Container2AnimationStartPositionProperty, ref _container2AnimationStartPosition, value);
+                set => SetAndRaise(Container2AnimationStartPositionProperty, ref _container2AnimationStartPosition,
+                    value);
             }
-
-            public double Container2Width
+            
+            /// <summary>
+            /// Used by <see cref="Avalonia.Themes.Fluent"/> to define the second indeterminate indicator's end position when animated.
+            /// </summary>
+            public double Container2AnimationEndPosition
             {
-                get => _container2Width;
-                set => SetAndRaise(Container2WidthProperty, ref _container2Width, value);
+                get => _container2AnimationEndPosition;
+                set => SetAndRaise(Container2AnimationEndPositionProperty, ref _container2AnimationEndPosition, value);
             }
 
-            public double ContainerWidth
+            /// <summary>
+            /// Used by <see cref="Avalonia.Themes.Simple"/>  to define the starting point of its indeterminate animation.
+            /// </summary>
+            public double IndeterminateStartingOffset
             {
-                get => _containerWidth;
-                set => SetAndRaise(ContainerWidthProperty, ref _containerWidth, value);
+                get => _indeterminateStartingOffset;
+                set => SetAndRaise(IndeterminateStartingOffsetProperty, ref _indeterminateStartingOffset, value);
             }
-
-            public double Container2AnimationEndPosition
+            
+            /// <summary>
+            /// Used by <see cref="Avalonia.Themes.Simple"/> to define the ending point of its indeterminate animation.
+            /// </summary>
+            public double IndeterminateEndingOffset
             {
-                get => _container2AnimationEndPosition;
-                set => SetAndRaise(Container2AnimationEndPositionProperty, ref _container2AnimationEndPosition, value);
+                get => _indeterminateEndingOffset;
+                set => SetAndRaise(IndeterminateEndingOffsetProperty, ref _indeterminateEndingOffset, value);
             }
         }
 
@@ -131,7 +211,7 @@ namespace Avalonia.Controls
         /// Defines the <see cref="Orientation"/> property.
         /// </summary>
         public static readonly StyledProperty<Orientation> OrientationProperty =
-            AvaloniaProperty.Register<ProgressBar, Orientation>(nameof(Orientation), Orientation.Horizontal);
+            AvaloniaProperty.Register<ProgressBar, Orientation>(nameof(Orientation));
 
         /// <summary>
         /// Defines the <see cref="Percentage"/> property.
@@ -141,18 +221,6 @@ namespace Avalonia.Controls
                 nameof(Percentage),
                 o => o.Percentage);
 
-        /// <summary>
-        /// Defines the <see cref="IndeterminateStartingOffset"/> property.
-        /// </summary>
-        public static readonly StyledProperty<double> IndeterminateStartingOffsetProperty =
-            AvaloniaProperty.Register<ProgressBar, double>(nameof(IndeterminateStartingOffset));
-
-        /// <summary>
-        /// Defines the <see cref="IndeterminateEndingOffset"/> property.
-        /// </summary>
-        public static readonly StyledProperty<double> IndeterminateEndingOffsetProperty =
-            AvaloniaProperty.Register<ProgressBar, double>(nameof(IndeterminateEndingOffset));
-
         /// <summary>
         /// Gets the overall percentage complete of the progress 
         /// </summary>
@@ -162,30 +230,13 @@ namespace Avalonia.Controls
         /// </remarks>
         public double Percentage
         {
-            get { return _percentage; }
+            get => _percentage;
             private set { SetAndRaise(PercentageProperty, ref _percentage, value); }
         }
 
-        public double IndeterminateStartingOffset
-        {
-            get => GetValue(IndeterminateStartingOffsetProperty);
-            set => SetValue(IndeterminateStartingOffsetProperty, value);
-        }
-
-        public double IndeterminateEndingOffset
-        {
-            get => GetValue(IndeterminateEndingOffsetProperty);
-            set => SetValue(IndeterminateEndingOffsetProperty, value);
-        }
-
         static ProgressBar()
         {
             ValueProperty.OverrideMetadata<ProgressBar>(new(defaultBindingMode: BindingMode.OneWay));
-            ValueProperty.Changed.AddClassHandler<ProgressBar>((x, e) => x.UpdateIndicatorWhenPropChanged(e));
-            MinimumProperty.Changed.AddClassHandler<ProgressBar>((x, e) => x.UpdateIndicatorWhenPropChanged(e));
-            MaximumProperty.Changed.AddClassHandler<ProgressBar>((x, e) => x.UpdateIndicatorWhenPropChanged(e));
-            IsIndeterminateProperty.Changed.AddClassHandler<ProgressBar>((x, e) => x.UpdateIndicatorWhenPropChanged(e));
-            OrientationProperty.Changed.AddClassHandler<ProgressBar>((x, e) => x.UpdateIndicatorWhenPropChanged(e));
         }
 
         /// <summary>
@@ -251,6 +302,15 @@ namespace Avalonia.Controls
         {
             base.OnPropertyChanged(change);
 
+            if (change.Property == ValueProperty ||
+                change.Property == MinimumProperty ||
+                change.Property == MaximumProperty ||
+                change.Property == IsIndeterminateProperty ||
+                change.Property == OrientationProperty)
+            {
+                UpdateIndicator();
+            }
+
             if (change.Property == IsIndeterminateProperty)
             {
                 UpdatePseudoClasses(change.GetNewValue<bool>(), null);
@@ -286,64 +346,50 @@ namespace Avalonia.Controls
             // Gets the size of the parent indicator container
             var barSize = _indicator?.VisualParent?.Bounds.Size ?? Bounds.Size;
 
-            if (_indicator != null)
+            if (_indicator == null) return;
+            if (IsIndeterminate)
             {
-                if (IsIndeterminate)
-                {
-                    // Pulled from ModernWPF.
+                // Pulled from ModernWPF.
 
-                    var dim = Orientation == Orientation.Horizontal ? barSize.Width : barSize.Height;
-                    var barIndicatorWidth = dim * 0.4; // Indicator width at 40% of ProgressBar
-                    var barIndicatorWidth2 = dim * 0.6; // Indicator width at 60% of ProgressBar
+                var dim = Orientation == Orientation.Horizontal ? barSize.Width : barSize.Height;
+                var barIndicatorWidth = dim * 0.4; // Indicator width at 40% of ProgressBar
+                var barIndicatorWidth2 = dim * 0.6; // Indicator width at 60% of ProgressBar
 
-                    TemplateSettings.ContainerWidth = barIndicatorWidth;
-                    TemplateSettings.Container2Width = barIndicatorWidth2;
+                TemplateSettings.ContainerWidth = barIndicatorWidth;
+                TemplateSettings.Container2Width = barIndicatorWidth2;
 
-                    TemplateSettings.ContainerAnimationStartPosition = barIndicatorWidth * -1.8; // Position at -180%
-                    TemplateSettings.ContainerAnimationEndPosition = barIndicatorWidth * 3.0; // Position at 300%
+                TemplateSettings.ContainerAnimationStartPosition = barIndicatorWidth * -1.8; // Position at -180%
+                TemplateSettings.ContainerAnimationEndPosition = barIndicatorWidth * 3.0; // Position at 300%
 
-                    TemplateSettings.Container2AnimationStartPosition = barIndicatorWidth2 * -1.5; // Position at -150%
-                    TemplateSettings.Container2AnimationEndPosition = barIndicatorWidth2 * 1.66; // Position at 166%
+                TemplateSettings.Container2AnimationStartPosition = barIndicatorWidth2 * -1.5; // Position at -150%
+                TemplateSettings.Container2AnimationEndPosition = barIndicatorWidth2 * 1.66; // Position at 166%
 
-                    // Remove these properties when we switch to fluent as default and removed the old one.
-                    SetCurrentValue(IndeterminateStartingOffsetProperty,-dim);
-                    SetCurrentValue(IndeterminateEndingOffsetProperty,dim);
+                TemplateSettings.IndeterminateStartingOffset = -dim;
+                TemplateSettings.IndeterminateEndingOffset = dim;
+            }
+            else
+            {
+                var percent = Math.Abs(Maximum - Minimum) < double.Epsilon ?
+                    1.0 :
+                    (Value - Minimum) / (Maximum - Minimum);
 
-                    var padding = Padding;
-                    var rectangle = new RectangleGeometry(
-                        new Rect(
-                            padding.Left,
-                            padding.Top,
-                            barSize.Width - (padding.Right + padding.Left),
-                            barSize.Height - (padding.Bottom + padding.Top)
-                            ));
+                // When the Orientation changed, the indicator's Width or Height should set to double.NaN.
+                // Indicator size calculation should consider the ProgressBar's Padding property setting
+                if (Orientation == Orientation.Horizontal)
+                {
+                    _indicator.Width = (barSize.Width - _indicator.Margin.Left - _indicator.Margin.Right) * percent;
+                    _indicator.Height = double.NaN;
                 }
                 else
                 {
-                    double percent = Maximum == Minimum ? 1.0 : (Value - Minimum) / (Maximum - Minimum);
-
-                    // When the Orientation changed, the indicator's Width or Height should set to double.NaN.
-                    // Indicator size calculation should consider the ProgressBar's Padding property setting
-                    if (Orientation == Orientation.Horizontal)
-                    {
-                        _indicator.Width = (barSize.Width - _indicator.Margin.Left - _indicator.Margin.Right) * percent;
-                        _indicator.Height = double.NaN;
-                    }
-                    else
-                    {
-                        _indicator.Width = double.NaN;
-                        _indicator.Height = (barSize.Height - _indicator.Margin.Top - _indicator.Margin.Bottom) * percent;
-                    }
-
-
-                    Percentage = percent * 100;
+                    _indicator.Width = double.NaN;
+                    _indicator.Height = (barSize.Height - _indicator.Margin.Top - _indicator.Margin.Bottom) *
+                                        percent;
                 }
-            }
-        }
 
-        private void UpdateIndicatorWhenPropChanged(AvaloniaPropertyChangedEventArgs e)
-        {
-            UpdateIndicator();
+
+                Percentage = percent * 100;
+            }
         }
 
         private void UpdatePseudoClasses(
@@ -355,11 +401,9 @@ namespace Avalonia.Controls
                 PseudoClasses.Set(":indeterminate", isIndeterminate.Value);
             }
 
-            if (o.HasValue)
-            {
-                PseudoClasses.Set(":vertical", o == Orientation.Vertical);
-                PseudoClasses.Set(":horizontal", o == Orientation.Horizontal);
-            }
+            if (!o.HasValue) return;
+            PseudoClasses.Set(":vertical", o == Orientation.Vertical);
+            PseudoClasses.Set(":horizontal", o == Orientation.Horizontal);
         }
     }
 }
diff --git a/src/Avalonia.Controls/PullToRefresh/RefreshVisualizer.cs b/src/Avalonia.Controls/PullToRefresh/RefreshVisualizer.cs
index ed419ad89b..5c7071a161 100644
--- a/src/Avalonia.Controls/PullToRefresh/RefreshVisualizer.cs
+++ b/src/Avalonia.Controls/PullToRefresh/RefreshVisualizer.cs
@@ -193,7 +193,7 @@ namespace Avalonia.Controls
                         UpdateContent();
                     };
 
-                    Content = _content;
+                    SetCurrentValue(ContentProperty, _content);
                 }
                 else
                 {
diff --git a/src/Avalonia.Controls/Remote/Server/RemoteServerTopLevelImpl.cs b/src/Avalonia.Controls/Remote/Server/RemoteServerTopLevelImpl.cs
index 58b0ed169c..8e4123a790 100644
--- a/src/Avalonia.Controls/Remote/Server/RemoteServerTopLevelImpl.cs
+++ b/src/Avalonia.Controls/Remote/Server/RemoteServerTopLevelImpl.cs
@@ -41,13 +41,7 @@ namespace Avalonia.Controls.Remote.Server
 
             KeyboardDevice = AvaloniaLocator.Current.GetRequiredService<IKeyboardDevice>();
             QueueNextRender();
-        }
-
-        IRenderer ITopLevelImpl.CreateRenderer(IRenderRoot root)
-        {
-            var r = (IRendererWithCompositor)base.CreateRenderer(root);
-            r.Compositor.AfterCommit += QueueNextRender;
-            return r;
+            Compositor.AfterCommit += QueueNextRender;
         }
 
         private static RawPointerEventType GetAvaloniaEventType(ProtocolMouseButton button, bool pressed)
diff --git a/src/Avalonia.Controls/ScrollViewer.cs b/src/Avalonia.Controls/ScrollViewer.cs
index 1b9cb7de34..31c4a7e399 100644
--- a/src/Avalonia.Controls/ScrollViewer.cs
+++ b/src/Avalonia.Controls/ScrollViewer.cs
@@ -644,7 +644,7 @@ namespace Avalonia.Controls
             (Presenter as IScrollAnchorProvider)?.UnregisterAnchorCandidate(element);
         }
 
-        protected override bool RegisterContentPresenter(IContentPresenter presenter)
+        protected override bool RegisterContentPresenter(ContentPresenter presenter)
         {
             _childSubscription?.Dispose();
             _childSubscription = null;
diff --git a/src/Avalonia.Controls/Shapes/Shape.cs b/src/Avalonia.Controls/Shapes/Shape.cs
index 461dc1c947..a65ac774ef 100644
--- a/src/Avalonia.Controls/Shapes/Shape.cs
+++ b/src/Avalonia.Controls/Shapes/Shape.cs
@@ -126,8 +126,8 @@ namespace Avalonia.Controls.Shapes
         /// </summary>
         public IBrush? Fill
         {
-            get { return GetValue(FillProperty); }
-            set { SetValue(FillProperty, value); }
+            get => GetValue(FillProperty);
+            set => SetValue(FillProperty, value);
         }
 
         /// <summary>
@@ -135,8 +135,8 @@ namespace Avalonia.Controls.Shapes
         /// </summary>
         public Stretch Stretch
         {
-            get { return GetValue(StretchProperty); }
-            set { SetValue(StretchProperty, value); }
+            get => GetValue(StretchProperty);
+            set => SetValue(StretchProperty, value);
         }
 
         /// <summary>
@@ -144,8 +144,8 @@ namespace Avalonia.Controls.Shapes
         /// </summary>
         public IBrush? Stroke
         {
-            get { return GetValue(StrokeProperty); }
-            set { SetValue(StrokeProperty, value); }
+            get => GetValue(StrokeProperty);
+            set => SetValue(StrokeProperty, value);
         }
 
         /// <summary>
@@ -153,8 +153,8 @@ namespace Avalonia.Controls.Shapes
         /// </summary>
         public AvaloniaList<double>? StrokeDashArray
         {
-            get { return GetValue(StrokeDashArrayProperty); }
-            set { SetValue(StrokeDashArrayProperty, value); }
+            get => GetValue(StrokeDashArrayProperty);
+            set => SetValue(StrokeDashArrayProperty, value);
         }
 
         /// <summary>
@@ -162,8 +162,8 @@ namespace Avalonia.Controls.Shapes
         /// </summary>
         public double StrokeDashOffset
         {
-            get { return GetValue(StrokeDashOffsetProperty); }
-            set { SetValue(StrokeDashOffsetProperty, value); }
+            get => GetValue(StrokeDashOffsetProperty);
+            set => SetValue(StrokeDashOffsetProperty, value);
         }
 
         /// <summary>
@@ -171,8 +171,8 @@ namespace Avalonia.Controls.Shapes
         /// </summary>
         public double StrokeThickness
         {
-            get { return GetValue(StrokeThicknessProperty); }
-            set { SetValue(StrokeThicknessProperty, value); }
+            get => GetValue(StrokeThicknessProperty);
+            set => SetValue(StrokeThicknessProperty, value);
         }
 
         /// <summary>
@@ -180,8 +180,8 @@ namespace Avalonia.Controls.Shapes
         /// </summary>
         public PenLineCap StrokeLineCap
         {
-            get { return GetValue(StrokeLineCapProperty); }
-            set { SetValue(StrokeLineCapProperty, value); }
+            get => GetValue(StrokeLineCapProperty);
+            set => SetValue(StrokeLineCapProperty, value);
         }
 
         /// <summary>
@@ -189,8 +189,8 @@ namespace Avalonia.Controls.Shapes
         /// </summary>
         public PenLineJoin StrokeJoin
         {
-            get { return GetValue(StrokeJoinProperty); }
-            set { SetValue(StrokeJoinProperty, value); }
+            get => GetValue(StrokeJoinProperty);
+            set => SetValue(StrokeJoinProperty, value);
         }
 
         public sealed override void Render(DrawingContext context)
diff --git a/src/Avalonia.Controls/SplitView/SplitView.cs b/src/Avalonia.Controls/SplitView/SplitView.cs
index b943a01a4b..fed0367d12 100644
--- a/src/Avalonia.Controls/SplitView/SplitView.cs
+++ b/src/Avalonia.Controls/SplitView/SplitView.cs
@@ -279,7 +279,7 @@ namespace Avalonia.Controls
             remove => RemoveHandler(PaneOpeningEvent, value);
         }
 
-        protected override bool RegisterContentPresenter(IContentPresenter presenter)
+        protected override bool RegisterContentPresenter(ContentPresenter presenter)
         {
             var result = base.RegisterContentPresenter(presenter);
 
diff --git a/src/Avalonia.Controls/TabControl.cs b/src/Avalonia.Controls/TabControl.cs
index b86624ead8..2b3a00cf3e 100644
--- a/src/Avalonia.Controls/TabControl.cs
+++ b/src/Avalonia.Controls/TabControl.cs
@@ -10,6 +10,7 @@ using Avalonia.LogicalTree;
 using Avalonia.VisualTree;
 using Avalonia.Automation;
 using Avalonia.Controls.Metadata;
+using Avalonia.Reactive;
 
 namespace Avalonia.Controls
 {
@@ -19,6 +20,10 @@ namespace Avalonia.Controls
     [TemplatePart("PART_ItemsPresenter", typeof(ItemsPresenter))]
     public class TabControl : SelectingItemsControl, IContentPresenterHost
     {
+        private object? _selectedContent;
+        private IDataTemplate? _selectedContentTemplate;
+        private CompositeDisposable? _selectedItemSubscriptions;
+
         /// <summary>
         /// Defines the <see cref="TabStripPlacement"/> property.
         /// </summary>
@@ -46,14 +51,14 @@ namespace Avalonia.Controls
         /// <summary>
         /// The selected content property
         /// </summary>
-        public static readonly StyledProperty<object?> SelectedContentProperty =
-            AvaloniaProperty.Register<TabControl, object?>(nameof(SelectedContent));
+        public static readonly DirectProperty<TabControl, object?> SelectedContentProperty =
+            AvaloniaProperty.RegisterDirect<TabControl, object?>(nameof(SelectedContent), o => o.SelectedContent);
 
         /// <summary>
         /// The selected content template property
         /// </summary>
-        public static readonly StyledProperty<IDataTemplate?> SelectedContentTemplateProperty =
-            AvaloniaProperty.Register<TabControl, IDataTemplate?>(nameof(SelectedContentTemplate));
+        public static readonly DirectProperty<TabControl, IDataTemplate?> SelectedContentTemplateProperty =
+            AvaloniaProperty.RegisterDirect<TabControl, IDataTemplate?>(nameof(SelectedContentTemplate), o => o.SelectedContentTemplate);
         
         /// <summary>
         /// The default value for the <see cref="ItemsControl.ItemsPanel"/> property.
@@ -115,11 +120,10 @@ namespace Avalonia.Controls
         /// <value>
         /// The content of the selected tab.
         /// </value>
-        [System.Diagnostics.CodeAnalysis.SuppressMessage("AvaloniaProperty", "AVP1032", Justification = "This property is supposed to be a styled readonly property.")]
         public object? SelectedContent
         {
-            get { return GetValue(SelectedContentProperty); }
-            internal set { SetValue(SelectedContentProperty, value); }
+            get => _selectedContent;
+            internal set => SetAndRaise(SelectedContentProperty, ref _selectedContent, value);
         }
 
         /// <summary>
@@ -128,22 +132,21 @@ namespace Avalonia.Controls
         /// <value>
         /// The content template of the selected tab.
         /// </value>
-        [System.Diagnostics.CodeAnalysis.SuppressMessage("AvaloniaProperty", "AVP1032", Justification = "This property is supposed to be a styled readonly property.")]
         public IDataTemplate? SelectedContentTemplate
         {
-            get { return GetValue(SelectedContentTemplateProperty); }
-            internal set { SetValue(SelectedContentTemplateProperty, value); }
+            get => _selectedContentTemplate;
+            internal set => SetAndRaise(SelectedContentTemplateProperty, ref _selectedContentTemplate, value);
         }
 
         internal ItemsPresenter? ItemsPresenterPart { get; private set; }
 
-        internal IContentPresenter? ContentPart { get; private set; }
+        internal ContentPresenter? ContentPart { get; private set; }
 
         /// <inheritdoc/>
         IAvaloniaList<ILogical> IContentPresenterHost.LogicalChildren => LogicalChildren;
 
         /// <inheritdoc/>
-        bool IContentPresenterHost.RegisterContentPresenter(IContentPresenter presenter)
+        bool IContentPresenterHost.RegisterContentPresenter(ContentPresenter presenter)
         {
             return RegisterContentPresenter(presenter);
         }
@@ -161,18 +164,10 @@ namespace Avalonia.Controls
         protected internal override void PrepareContainerForItemOverride(Control element, object? item, int index)
         {
             base.PrepareContainerForItemOverride(element, item, index);
-            
-            if (element is TabItem tabItem)
-            {
-                if (ContentTemplate is { } ct)
-                    tabItem.ContentTemplate = ct;
-                tabItem.SetValue(TabStripPlacementProperty, TabStripPlacement);
-            }
 
-            if (index == SelectedIndex && element is ContentControl container)
+            if (index == SelectedIndex)
             {
-                SelectedContentTemplate = container.ContentTemplate;
-                SelectedContent = container.Content;
+                UpdateSelectedContent(element);
             }
         }
 
@@ -192,26 +187,33 @@ namespace Avalonia.Controls
             UpdateSelectedContent();
         }
 
-        private void UpdateSelectedContent()
+        private void UpdateSelectedContent(Control? container = null)
         {
+            _selectedItemSubscriptions?.Dispose();
+            _selectedItemSubscriptions = null;
+
             if (SelectedIndex == -1)
             {
                 SelectedContent = SelectedContentTemplate = null;
             }
             else
             {
-                var container = SelectedItem as IContentControl ??
-                    ContainerFromIndex(SelectedIndex) as IContentControl;
-                SelectedContentTemplate = container?.ContentTemplate;
-                SelectedContent = container?.Content;
+                container ??= ContainerFromIndex(SelectedIndex);
+                if (container != null)
+                {
+                    _selectedItemSubscriptions = new CompositeDisposable(
+                        container.GetObservable(ContentControl.ContentProperty).Subscribe(v => SelectedContent = v),
+                        // Note how we fall back to our own ContentTemplate if the container doesn't specify one
+                        container.GetObservable(ContentControl.ContentTemplateProperty).Subscribe(v => SelectedContentTemplate = v ?? ContentTemplate));
+                }
             }
         }
 
         /// <summary>
-        /// Called when an <see cref="IContentPresenter"/> is registered with the control.
+        /// Called when an <see cref="ContentPresenter"/> is registered with the control.
         /// </summary>
         /// <param name="presenter">The presenter.</param>
-        protected virtual bool RegisterContentPresenter(IContentPresenter presenter)
+        protected virtual bool RegisterContentPresenter(ContentPresenter presenter)
         {
             if (presenter.Name == "PART_SelectedContentHost")
             {
@@ -224,7 +226,7 @@ namespace Avalonia.Controls
 
         protected override void OnApplyTemplate(TemplateAppliedEventArgs e)
         {
-            ItemsPresenterPart = e.NameScope.Get<ItemsPresenter>("PART_ItemsPresenter");
+            ItemsPresenterPart = e.NameScope.Find<ItemsPresenter>("PART_ItemsPresenter");
             ItemsPresenterPart?.ApplyTemplate();
 
             // Set TabNavigation to Once on the panel if not already set and
@@ -285,6 +287,16 @@ namespace Avalonia.Controls
             {
                 RefreshContainers();
             }
+            else if (change.Property == ContentTemplateProperty)
+            {
+                var newTemplate = change.GetNewValue<IDataTemplate?>();
+                if (SelectedContentTemplate != newTemplate &&
+                    ContainerFromIndex(SelectedIndex) is { } container && 
+                    container.GetValue(ContentControl.ContentTemplateProperty) == null)
+                {
+                    SelectedContentTemplate = newTemplate; // See also UpdateSelectedContent
+                }
+            }
             else if (change.Property == KeyboardNavigation.TabOnceActiveElementProperty &&
                 ItemsPresenterPart?.Panel is { } panel)
             {
diff --git a/src/Avalonia.Controls/TabItem.cs b/src/Avalonia.Controls/TabItem.cs
index 4068404952..7a3465b1a4 100644
--- a/src/Avalonia.Controls/TabItem.cs
+++ b/src/Avalonia.Controls/TabItem.cs
@@ -1,22 +1,28 @@
+using System;
 using Avalonia.Automation;
 using Avalonia.Automation.Peers;
 using Avalonia.Controls.Metadata;
 using Avalonia.Controls.Mixins;
 using Avalonia.Controls.Primitives;
+using Avalonia.Reactive;
+using Avalonia.VisualTree;
 
 namespace Avalonia.Controls
 {
     /// <summary>
-    /// An item in  a <see cref="TabStrip"/> or <see cref="TabControl"/>.
+    /// An item in a <see cref="TabControl"/>.
     /// </summary>
     [PseudoClasses(":pressed", ":selected")]
     public class TabItem : HeaderedContentControl, ISelectable
     {
+        private Dock? _tabStripPlacement;
+        private IDisposable? _ownerSubscriptions;
+
         /// <summary>
         /// Defines the <see cref="TabStripPlacement"/> property.
         /// </summary>
-        public static readonly StyledProperty<Dock> TabStripPlacementProperty =
-            TabControl.TabStripPlacementProperty.AddOwner<TabItem>();
+        public static readonly DirectProperty<TabItem, Dock?> TabStripPlacementProperty =
+            AvaloniaProperty.RegisterDirect<TabItem, Dock?>(nameof(TabStripPlacement), o => o.TabStripPlacement);
 
         /// <summary>
         /// Defines the <see cref="IsSelected"/> property.
@@ -37,16 +43,12 @@ namespace Avalonia.Controls
         }
 
         /// <summary>
-        /// Gets the tab strip placement.
+        /// Gets the placement of this tab relative to the outer <see cref="TabControl"/>, if there is one.
         /// </summary>
-        /// <value>
-        /// The tab strip placement.
-        /// </value>
-        [System.Diagnostics.CodeAnalysis.SuppressMessage("AvaloniaProperty", "AVP1031",
-            Justification = "This property is supposed to be inherited only and settable on parent TabControl.")]
-        public Dock TabStripPlacement
+        public Dock? TabStripPlacement
         {
-            get { return GetValue(TabStripPlacementProperty); }
+            get => _tabStripPlacement;
+            private set => SetAndRaise(TabStripPlacementProperty, ref _tabStripPlacement, value);
         }
 
         /// <summary>
@@ -60,6 +62,24 @@ namespace Avalonia.Controls
 
         protected override AutomationPeer OnCreateAutomationPeer() => new ListItemAutomationPeer(this);
 
+        protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
+        {
+            base.OnAttachedToVisualTree(e);
+
+            _ownerSubscriptions?.Dispose();
+            _ownerSubscriptions = null;
+
+            if (this.FindAncestorOfType<TabControl>() is { } owner && owner.IndexFromContainer(this) != -1)
+            {
+                SubscribeToOwnerProperties(owner);
+            }
+        }
+
+        protected void SubscribeToOwnerProperties(AvaloniaObject owner)
+        {
+            _ownerSubscriptions = owner.GetObservable(TabControl.TabStripPlacementProperty).Subscribe(v => TabStripPlacement = v);
+        }
+
         private void UpdateHeader(AvaloniaPropertyChangedEventArgs obj)
         {
             if (Header == null)
diff --git a/src/Avalonia.Controls/TextBlock.cs b/src/Avalonia.Controls/TextBlock.cs
index 6144136882..57d709ba94 100644
--- a/src/Avalonia.Controls/TextBlock.cs
+++ b/src/Avalonia.Controls/TextBlock.cs
@@ -639,8 +639,7 @@ namespace Avalonia.Controls
                 TextTrimming,
                 _constraint.Width,
                 _constraint.Height,
-                maxLines: MaxLines,
-                lineHeight: LineHeight);
+                MaxLines);
         }
 
         /// <summary>
diff --git a/src/Avalonia.Controls/TextBox.cs b/src/Avalonia.Controls/TextBox.cs
index 51a7fe9b7f..7bc26bf3b0 100644
--- a/src/Avalonia.Controls/TextBox.cs
+++ b/src/Avalonia.Controls/TextBox.cs
@@ -18,9 +18,6 @@ using Avalonia.Media.TextFormatting;
 using Avalonia.Media.TextFormatting.Unicode;
 using Avalonia.Automation.Peers;
 using Avalonia.Threading;
-using Avalonia.Platform;
-using System.Reflection;
-using static System.Net.Mime.MediaTypeNames;
 
 namespace Avalonia.Controls
 {
@@ -28,6 +25,7 @@ namespace Avalonia.Controls
     /// Represents a control that can be used to display or edit unformatted text.
     /// </summary>
     [TemplatePart("PART_TextPresenter", typeof(TextPresenter))]
+    [TemplatePart("PART_ScrollViewer", typeof(ScrollViewer))]
     [PseudoClasses(":empty")]
     public class TextBox : TemplatedControl, UndoRedoHelper<TextBox.UndoRedoState>.IUndoRedoHost
     {
@@ -158,7 +156,7 @@ namespace Avalonia.Controls
         /// Defines see <see cref="TextPresenter.LineHeight"/> property.
         /// </summary>
         public static readonly StyledProperty<double> LineHeightProperty =
-            TextBlock.LineHeightProperty.AddOwner<TextBox>();
+            TextBlock.LineHeightProperty.AddOwner<TextBox>(new(defaultValue: double.NaN));
 
         /// <summary>
         /// Defines see <see cref="TextBlock.LetterSpacing"/> property.
@@ -310,6 +308,7 @@ namespace Avalonia.Controls
         }
 
         private TextPresenter? _presenter;
+        private ScrollViewer? _scrollViewer;
         private readonly TextBoxTextInputMethodClient _imClient = new();
         private readonly UndoRedoHelper<UndoRedoState> _undoRedoHelper;
         private bool _isUndoingRedoing;
@@ -490,7 +489,7 @@ namespace Avalonia.Controls
         }
 
         /// <summary>
-        /// Gets or sets the maximum character length of the TextBox
+        /// Gets or sets the maximum number of visible lines.
         /// </summary>
         public int MaxLength
         {
@@ -803,6 +802,8 @@ namespace Avalonia.Controls
         {
             _presenter = e.NameScope.Get<TextPresenter>("PART_TextPresenter");
 
+            _scrollViewer = e.NameScope.Find<ScrollViewer>("PART_ScrollViewer");
+
             _imClient.SetPresenter(_presenter, this);
 
             if (IsFocused)
@@ -855,6 +856,10 @@ namespace Avalonia.Controls
             {
                 OnSelectionEndChanged(change);
             }
+            else if (change.Property == MaxLinesProperty)
+            {
+                InvalidateMeasure();
+            }
             else if (change.Property == UndoLimitProperty)
             {
                 OnUndoLimitChanged(change.GetNewValue<int>());
@@ -942,40 +947,10 @@ namespace Avalonia.Controls
             {
                 return;
             }
+
             _selectedTextChangesMadeSinceLastUndoSnapshot++;
             SnapshotUndoRedo(ignoreChangeCount: false);
 
-            if (_presenter != null && MaxLines > 0)
-            {
-                var lineCount = _presenter.TextLayout.TextLines.Count;
-
-                var length = 0;
-
-                var graphemeEnumerator = new GraphemeEnumerator(input.AsSpan());
-
-                while (graphemeEnumerator.MoveNext(out var grapheme))
-                {
-                    if (grapheme.FirstCodepoint.IsBreakChar)
-                    {
-                        if (lineCount + 1 > MaxLines)
-                        {
-                            break;
-                        }
-                        else
-                        {
-                            lineCount++;
-                        }
-                    }
-
-                    length += grapheme.Length;
-                }
-
-                if (length < input.Length)
-                {
-                    input = input.Remove(Math.Max(0, length));
-                }
-            }
-
             var currentText = Text ?? string.Empty;
             var selectionLength = Math.Abs(SelectionStart - SelectionEnd);
             var newLength = input.Length + currentText.Length - selectionLength;
@@ -1518,7 +1493,7 @@ namespace Avalonia.Controls
                 _presenter.MoveCaretToPoint(point);
 
                 var caretIndex = _presenter.CaretIndex;
-         
+
                 var selectionStart = SelectionStart;
                 var selectionEnd = SelectionEnd;
 
@@ -1976,5 +1951,47 @@ namespace Avalonia.Controls
         {
             CanRedo = _undoRedoHelper.CanRedo;
         }
+
+        protected override Size MeasureOverride(Size availableSize)
+        {
+            if(_scrollViewer != null)
+            {
+                var maxHeight = double.PositiveInfinity;
+
+                if (MaxLines > 0 && double.IsNaN(Height))
+                {
+                    var fontSize = FontSize;
+                    var typeface = new Typeface(FontFamily, FontStyle, FontWeight, FontStretch);
+                    var paragraphProperties = TextLayout.CreateTextParagraphProperties(typeface, fontSize, null, default, default, null, default, LineHeight, default);
+                    var textLayout = new TextLayout(new MaxLinesTextSource(MaxLines), paragraphProperties);
+
+                    maxHeight = Math.Ceiling(textLayout.Height);
+                }
+
+                _scrollViewer.SetCurrentValue(MaxHeightProperty, maxHeight);
+            }
+
+            return base.MeasureOverride(availableSize);
+        }
+
+        private class MaxLinesTextSource : ITextSource
+        {
+            private readonly int _maxLines;
+
+            public MaxLinesTextSource(int maxLines)
+            {
+                _maxLines = maxLines;
+            }
+
+            public TextRun? GetTextRun(int textSourceIndex)
+            {
+                if (textSourceIndex >= _maxLines)
+                {
+                    return null;
+                }
+
+                return new TextEndOfLine(1);
+            }
+        }
     }
 }
diff --git a/src/Avalonia.Controls/TextChangedEventArgs.cs b/src/Avalonia.Controls/TextChangedEventArgs.cs
index 1418154256..f614d2d760 100644
--- a/src/Avalonia.Controls/TextChangedEventArgs.cs
+++ b/src/Avalonia.Controls/TextChangedEventArgs.cs
@@ -3,15 +3,24 @@
 namespace Avalonia.Controls
 {
     /// <summary>
-    /// Provides data specific to a TextChanged event.
+    /// Provides data specific to a <see cref="TextBox.TextChanged"/> event.
     /// </summary>
     public class TextChangedEventArgs : RoutedEventArgs
     {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="TextChangedEventArgs"/> class.
+        /// </summary>
+        /// <param name="routedEvent">The routed event associated with these event args.</param>
         public TextChangedEventArgs(RoutedEvent? routedEvent)
             : base (routedEvent)
         {
         }
 
+        /// <summary>
+        /// Initializes a new instance of the <see cref="TextChangedEventArgs"/> class.
+        /// </summary>
+        /// <param name="routedEvent">The routed event associated with these event args.</param>
+        /// <param name="source">The source object that raised the routed event.</param>
         public TextChangedEventArgs(RoutedEvent? routedEvent, Interactive? source)
             : base(routedEvent, source)
         {
diff --git a/src/Avalonia.Controls/TextChangingEventArgs.cs b/src/Avalonia.Controls/TextChangingEventArgs.cs
index 09e7d5b258..6ec5afd030 100644
--- a/src/Avalonia.Controls/TextChangingEventArgs.cs
+++ b/src/Avalonia.Controls/TextChangingEventArgs.cs
@@ -3,15 +3,24 @@
 namespace Avalonia.Controls
 {
     /// <summary>
-    /// Provides data specific to a TextChanging event.
+    /// Provides data specific to a <see cref="TextBox.TextChanging"/> event.
     /// </summary>
     public class TextChangingEventArgs : RoutedEventArgs
     {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="TextChangingEventArgs"/> class.
+        /// </summary>
+        /// <param name="routedEvent">The routed event associated with these event args.</param>
         public TextChangingEventArgs(RoutedEvent? routedEvent)
             : base (routedEvent)
         {
         }
 
+        /// <summary>
+        /// Initializes a new instance of the <see cref="TextChangingEventArgs"/> class.
+        /// </summary>
+        /// <param name="routedEvent">The routed event associated with these event args.</param>
+        /// <param name="source">The source object that raised the routed event.</param>
         public TextChangingEventArgs(RoutedEvent? routedEvent, Interactive? source)
             : base(routedEvent, source)
         {
diff --git a/src/Avalonia.Controls/ToggleSwitch.cs b/src/Avalonia.Controls/ToggleSwitch.cs
index 29e1b90ca0..a68a022e67 100644
--- a/src/Avalonia.Controls/ToggleSwitch.cs
+++ b/src/Avalonia.Controls/ToggleSwitch.cs
@@ -86,13 +86,13 @@ namespace Avalonia.Controls
             set { SetValue(OffContentProperty, value); }
         }
 
-        public IContentPresenter? OffContentPresenter
+        public ContentPresenter? OffContentPresenter
         {
             get;
             private set;
         }
 
-        public IContentPresenter? OnContentPresenter
+        public ContentPresenter? OnContentPresenter
         {
             get;
             private set;
@@ -142,7 +142,7 @@ namespace Avalonia.Controls
             }
         }
 
-        protected override bool RegisterContentPresenter(IContentPresenter presenter)
+        protected override bool RegisterContentPresenter(ContentPresenter presenter)
         {
             var result = base.RegisterContentPresenter(presenter);
 
diff --git a/src/Avalonia.Controls/TopLevel.cs b/src/Avalonia.Controls/TopLevel.cs
index c7f1f45b5d..92444b9c07 100644
--- a/src/Avalonia.Controls/TopLevel.cs
+++ b/src/Avalonia.Controls/TopLevel.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.ComponentModel;
 using System.Diagnostics;
 using Avalonia.Reactive;
@@ -22,6 +23,8 @@ using Avalonia.Utilities;
 using Avalonia.Input.Platform;
 using System.Linq;
 using System.Threading.Tasks;
+using Avalonia.Metadata;
+using Avalonia.Rendering.Composition;
 
 namespace Avalonia.Controls
 {
@@ -64,8 +67,8 @@ namespace Avalonia.Controls
         /// <summary>
         /// Defines the <see cref="TransparencyLevelHint"/> property.
         /// </summary>
-        public static readonly StyledProperty<WindowTransparencyLevel> TransparencyLevelHintProperty =
-            AvaloniaProperty.Register<TopLevel, WindowTransparencyLevel>(nameof(TransparencyLevelHint), WindowTransparencyLevel.None);
+        public static readonly StyledProperty<IReadOnlyList<WindowTransparencyLevel>> TransparencyLevelHintProperty =
+            AvaloniaProperty.Register<TopLevel, IReadOnlyList<WindowTransparencyLevel>>(nameof(TransparencyLevelHint), Array.Empty<WindowTransparencyLevel>());
 
         /// <summary>
         /// Defines the <see cref="ActualTransparencyLevel"/> property.
@@ -172,7 +175,7 @@ namespace Avalonia.Controls
             PlatformImpl = impl ?? throw new InvalidOperationException(
                 "Could not create window implementation: maybe no windowing subsystem was initialized?");
 
-            _actualTransparencyLevel = PlatformImpl.TransparencyLevel;            
+            _actualTransparencyLevel = PlatformImpl.TransparencyLevel;
 
             dependencyResolver ??= AvaloniaLocator.Current;
 
@@ -182,7 +185,7 @@ namespace Avalonia.Controls
             _globalStyles = TryGetService<IGlobalStyles>(dependencyResolver);
             _applicationThemeHost = TryGetService<IThemeVariantHost>(dependencyResolver);
 
-            Renderer = impl.CreateRenderer(this);
+            Renderer = new CompositingRenderer(this, impl.Compositor, () => impl.Surfaces);
             Renderer.SceneInvalidated += SceneInvalidated;
 
             impl.SetInputRoot(this);
@@ -310,8 +313,11 @@ namespace Avalonia.Controls
 
         /// <summary>
         /// Gets or sets the <see cref="WindowTransparencyLevel"/> that the TopLevel should use when possible.
+        /// Accepts multiple values which are applied in a fallback order.
+        /// For instance, with "Mica, Blur" Mica will be applied only on platforms where it is possible,
+        /// and Blur will be used on the rest of them. Default value is an empty array or "None".    
         /// </summary>
-        public WindowTransparencyLevel TransparencyLevelHint
+        public IReadOnlyList<WindowTransparencyLevel> TransparencyLevelHint
         {
             get { return GetValue(TransparencyLevelHintProperty); }
             set { SetValue(TransparencyLevelHintProperty, value); }
@@ -352,7 +358,7 @@ namespace Avalonia.Controls
             remove { RemoveHandler(BackRequestedEvent, value); }
         }
 
-        public ILayoutManager LayoutManager
+        internal ILayoutManager LayoutManager
         {
             get
             {
@@ -371,6 +377,8 @@ namespace Avalonia.Controls
             }
         }
 
+        ILayoutManager ILayoutRoot.LayoutManager => LayoutManager;
+
         /// <summary>
         /// Gets the platform-specific window implementation.
         /// </summary>
@@ -388,7 +396,22 @@ namespace Avalonia.Controls
         /// <summary>
         /// Gets the renderer for the window.
         /// </summary>
-        public IRenderer Renderer { get; }
+        internal CompositingRenderer Renderer { get; }
+
+        internal IHitTester HitTester => HitTesterOverride ?? Renderer;
+
+        // This property setter is here purely for lazy unit tests
+        // that don't want to set up a proper hit-testable visual tree
+        // and should be removed after fixing those tests
+        internal IHitTester? HitTesterOverride;
+
+        IRenderer IRenderRoot.Renderer => Renderer;
+        IHitTester IRenderRoot.HitTester => HitTester;
+
+        /// <summary>
+        /// Gets a value indicating whether the renderer should draw specific diagnostics.
+        /// </summary>
+        public RendererDiagnostics RendererDiagnostics => Renderer.Diagnostics;
 
         internal PixelPoint? LastPointerPosition => _pointerOverPreProcessor?.LastPosition;
         
@@ -518,8 +541,8 @@ namespace Avalonia.Controls
             {
                 if (PlatformImpl != null)
                 {
-                    PlatformImpl.SetTransparencyLevelHint(change.GetNewValue<WindowTransparencyLevel>());
-                    HandleTransparencyLevelChanged(PlatformImpl.TransparencyLevel);
+                    PlatformImpl.SetTransparencyLevelHint(
+                        change.GetNewValue<IReadOnlyList<WindowTransparencyLevel>>() ?? Array.Empty<WindowTransparencyLevel>());
                 }
             }
             else if (change.Property == ActualThemeVariantProperty)
@@ -543,6 +566,10 @@ namespace Avalonia.Controls
             Renderer.Paint(rect);
         }
 
+        protected void StartRendering() => MediaContext.Instance.AddTopLevel(this, LayoutManager, Renderer);
+
+        protected void StopRendering() => MediaContext.Instance.RemoveTopLevel(this);
+
         /// <summary>
         /// Handles a closed notification from <see cref="ITopLevelImpl.Closed"/>.
         /// </summary>
@@ -610,27 +637,11 @@ namespace Avalonia.Controls
             ScalingChanged?.Invoke(this, EventArgs.Empty);
         }
 
-        private static bool TransparencyLevelsMatch (WindowTransparencyLevel requested, WindowTransparencyLevel received)
-        {
-            if(requested == received)
-            {
-                return true;
-            }
-            else if(requested >= WindowTransparencyLevel.Blur && received >= WindowTransparencyLevel.Blur)
-            {
-                return true;
-            }
-
-            return false;
-        }
-
         private void HandleTransparencyLevelChanged(WindowTransparencyLevel transparencyLevel)
         {
-            if(_transparencyFallbackBorder != null)
+            if (_transparencyFallbackBorder != null)
             {
-                if(transparencyLevel == WindowTransparencyLevel.None || 
-                    TransparencyLevelHint == WindowTransparencyLevel.None || 
-                    !TransparencyLevelsMatch(TransparencyLevelHint, transparencyLevel))
+                if (transparencyLevel == WindowTransparencyLevel.None)
                 {
                     _transparencyFallbackBorder.Background = TransparencyBackgroundFallback;
                 }
@@ -660,7 +671,6 @@ namespace Avalonia.Controls
                 return;
 
             _transparencyFallbackBorder = e.NameScope.Find<Border>("PART_TransparencyFallback");
-
             HandleTransparencyLevelChanged(PlatformImpl.TransparencyLevel);
         }
 
diff --git a/src/Avalonia.Controls/TransitioningContentControl.cs b/src/Avalonia.Controls/TransitioningContentControl.cs
index edc1b10d93..21b9c9b765 100644
--- a/src/Avalonia.Controls/TransitioningContentControl.cs
+++ b/src/Avalonia.Controls/TransitioningContentControl.cs
@@ -71,7 +71,7 @@ public class TransitioningContentControl : ContentControl
         return result;
     }
 
-    protected override bool RegisterContentPresenter(IContentPresenter presenter)
+    protected override bool RegisterContentPresenter(ContentPresenter presenter)
     {
         if (!base.RegisterContentPresenter(presenter) &&
             presenter is ContentPresenter p &&
diff --git a/src/Avalonia.Controls/Window.cs b/src/Avalonia.Controls/Window.cs
index e64341b735..42052b8d69 100644
--- a/src/Avalonia.Controls/Window.cs
+++ b/src/Avalonia.Controls/Window.cs
@@ -541,11 +541,11 @@ namespace Avalonia.Controls
 
             if (state == WindowState.Minimized)
             {
-                Renderer.Stop();
+                StopRendering();
             }
             else
             {
-                Renderer.Start();
+                StartRendering();
             }
         }
 
@@ -568,7 +568,7 @@ namespace Avalonia.Controls
                     return;
                 }
 
-                Renderer.Stop();
+                StopRendering();
 
                 if (Owner is Window owner)
                 {
@@ -716,7 +716,7 @@ namespace Avalonia.Controls
                 SetWindowStartupLocation(owner);
 
                 PlatformImpl?.Show(ShowActivated, false);
-                Renderer.Start();
+                StartRendering();
                 OnOpened(EventArgs.Empty);
             }
         }
@@ -793,7 +793,7 @@ namespace Avalonia.Controls
 
                 PlatformImpl?.Show(ShowActivated, true);
 
-                Renderer.Start();
+                StartRendering();
 
                 Observable.FromEventPattern(
                         x => Closed += x,
diff --git a/src/Avalonia.Controls/WindowBase.cs b/src/Avalonia.Controls/WindowBase.cs
index d219734fe0..1cc235ce99 100644
--- a/src/Avalonia.Controls/WindowBase.cs
+++ b/src/Avalonia.Controls/WindowBase.cs
@@ -149,7 +149,7 @@ namespace Avalonia.Controls
         {
             using (FreezeVisibilityChangeHandling())
             {
-                Renderer.Stop();
+                StopRendering();
                 PlatformImpl?.Hide();
                 IsVisible = false;
             }
@@ -173,7 +173,7 @@ namespace Avalonia.Controls
                 }
 
                 PlatformImpl?.Show(true, false);
-                Renderer.Start();
+                StartRendering();
                 OnOpened(EventArgs.Empty);
             }
         }
diff --git a/src/Avalonia.Controls/WindowTransparencyLevel.cs b/src/Avalonia.Controls/WindowTransparencyLevel.cs
index d463f74a0e..bce6e21e68 100644
--- a/src/Avalonia.Controls/WindowTransparencyLevel.cs
+++ b/src/Avalonia.Controls/WindowTransparencyLevel.cs
@@ -1,35 +1,51 @@
-namespace Avalonia.Controls
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+
+namespace Avalonia.Controls;
+
+public readonly record struct WindowTransparencyLevel
 {
-    public enum WindowTransparencyLevel
+    private readonly string _value;
+
+    private WindowTransparencyLevel(string value)
     {
-        /// <summary>
-        /// The window background is Black where nothing is drawn in the window.
-        /// </summary>
-        None,
-
-        /// <summary>
-        /// The window background is Transparent where nothing is drawn in the window.
-        /// </summary>
-        Transparent,
-
-        /// <summary>
-        /// The window background is a blur-behind where nothing is drawn in the window.
-        /// </summary>
-        Blur,
-
-        /// <summary>
-        /// The window background is a blur-behind with a high blur radius. This level may fallback to Blur.
-        /// </summary>
-        AcrylicBlur,
-        
-        /// <summary>
-        /// Force acrylic on some incompatible versions of Windows 10. 
-        /// </summary>
-        ForceAcrylicBlur,
-        
-        /// <summary>
-        /// The window background is based on desktop wallpaper tint with a blur. This will only work on Windows 11 
-        /// </summary>
-        Mica
+        _value = value;
+    }
+
+    /// <summary>
+    /// The window background is Black where nothing is drawn in the window.
+    /// </summary>
+    public static WindowTransparencyLevel None { get; } = new(nameof(None));
+
+    /// <summary>
+    /// The window background is Transparent where nothing is drawn in the window.
+    /// </summary>
+    public static WindowTransparencyLevel Transparent { get; } = new(nameof(Transparent));
+
+    /// <summary>
+    /// The window background is a blur-behind where nothing is drawn in the window.
+    /// </summary>
+    public static WindowTransparencyLevel Blur { get; } = new(nameof(Blur));
+
+    /// <summary>
+    /// The window background is a blur-behind with a high blur radius. This level may fallback to Blur.
+    /// </summary>
+    public static WindowTransparencyLevel AcrylicBlur { get; } = new(nameof(AcrylicBlur));
+
+    /// <summary>
+    /// The window background is based on desktop wallpaper tint with a blur. This will only work on Windows 11 
+    /// </summary>
+    public static WindowTransparencyLevel Mica { get; } = new(nameof(Mica));
+
+    public override string ToString()
+    {
+        return _value;
     }
 }
+
+public class WindowTransparencyLevelCollection : ReadOnlyCollection<WindowTransparencyLevel>
+{
+    public WindowTransparencyLevelCollection(IList<WindowTransparencyLevel> list) : base(list)
+    {
+    }
+} 
diff --git a/src/Avalonia.DesignerSupport/Remote/PreviewerWindowingPlatform.cs b/src/Avalonia.DesignerSupport/Remote/PreviewerWindowingPlatform.cs
index ab0a668607..d2787e73ae 100644
--- a/src/Avalonia.DesignerSupport/Remote/PreviewerWindowingPlatform.cs
+++ b/src/Avalonia.DesignerSupport/Remote/PreviewerWindowingPlatform.cs
@@ -52,7 +52,6 @@ namespace Avalonia.DesignerSupport.Remote
                 .Bind<IKeyboardDevice>().ToConstant(Keyboard)
                 .Bind<IPlatformSettings>().ToSingleton<DefaultPlatformSettings>()
                 .Bind<IDispatcherImpl>().ToConstant(new ManagedDispatcherImpl(null))
-                .Bind<IRenderLoop>().ToConstant(new RenderLoop())
                 .Bind<IRenderTimer>().ToConstant(new DefaultRenderTimer(60))
                 .Bind<IWindowingPlatform>().ToConstant(instance)
                 .Bind<IPlatformIconLoader>().ToSingleton<IconLoaderStub>()
diff --git a/src/Avalonia.DesignerSupport/Remote/Stubs.cs b/src/Avalonia.DesignerSupport/Remote/Stubs.cs
index f6f5c185e9..a1fc0e885d 100644
--- a/src/Avalonia.DesignerSupport/Remote/Stubs.cs
+++ b/src/Avalonia.DesignerSupport/Remote/Stubs.cs
@@ -69,10 +69,8 @@ namespace Avalonia.DesignerSupport.Remote
             public bool RunsInBackground => false;
         }
 
-        public IRenderer CreateRenderer(IRenderRoot root) =>
-            new CompositingRenderer(root,
-                new Compositor(new RenderLoop(new DummyRenderTimer(), Dispatcher.UIThread), null), () => Surfaces);
-        
+        public Compositor Compositor { get; } = new(new RenderLoop(new DummyRenderTimer()), null);
+
         public void Dispose()
         {
         }
@@ -179,13 +177,13 @@ namespace Avalonia.DesignerSupport.Remote
 
         public Action GotInputWhenDisabled { get; set; }
 
-        public void SetTransparencyLevelHint(WindowTransparencyLevel transparencyLevel) { }
+        public void SetTransparencyLevelHint(IReadOnlyList<WindowTransparencyLevel> transparencyLevel) { }
 
         public void SetWindowManagerAddShadowHint(bool enabled)
         {
         }
 
-        public WindowTransparencyLevel TransparencyLevel { get; private set; }
+        public WindowTransparencyLevel TransparencyLevel => WindowTransparencyLevel.None;
 
         public bool IsClientAreaExtendedToDecorations { get; }
 
diff --git a/src/Avalonia.Diagnostics/Diagnostics/Controls/Application.cs b/src/Avalonia.Diagnostics/Diagnostics/Controls/Application.cs
index 0791815120..06dbb7d50e 100644
--- a/src/Avalonia.Diagnostics/Diagnostics/Controls/Application.cs
+++ b/src/Avalonia.Diagnostics/Diagnostics/Controls/Application.cs
@@ -59,15 +59,6 @@ namespace Avalonia.Diagnostics.Controls
         public Avalonia.Controls.Templates.DataTemplates DataTemplates =>
             _application.DataTemplates;
 
-        /// <summary>
-        /// Gets the application's focus manager.
-        /// </summary>
-        /// <value>
-        /// The application's focus manager.
-        /// </value>
-        public Input.IFocusManager? FocusManager =>
-            _application.FocusManager;
-
         /// <summary>
         /// Gets the application's input manager.
         /// </summary>
diff --git a/src/Avalonia.Diagnostics/Diagnostics/Controls/FilterTextBox.axaml b/src/Avalonia.Diagnostics/Diagnostics/Controls/FilterTextBox.axaml
index 1b5f431f36..e5af7c51de 100644
--- a/src/Avalonia.Diagnostics/Diagnostics/Controls/FilterTextBox.axaml
+++ b/src/Avalonia.Diagnostics/Diagnostics/Controls/FilterTextBox.axaml
@@ -1,7 +1,8 @@
 <Styles xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:controls="using:Avalonia.Diagnostics.Controls"
-        x:DataType="controls:FilterTextBox">
+        x:DataType="controls:FilterTextBox"
+        x:ClassModifier="internal">
 
   <Design.PreviewWith>
     <Border Padding="10">
diff --git a/src/Avalonia.Diagnostics/Diagnostics/Controls/ThicknessEditor.axaml b/src/Avalonia.Diagnostics/Diagnostics/Controls/ThicknessEditor.axaml
index 3e0ddc4b4d..1ad6985070 100644
--- a/src/Avalonia.Diagnostics/Diagnostics/Controls/ThicknessEditor.axaml
+++ b/src/Avalonia.Diagnostics/Diagnostics/Controls/ThicknessEditor.axaml
@@ -1,6 +1,7 @@
 <Styles xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:controls="using:Avalonia.Diagnostics.Controls">
+        xmlns:controls="using:Avalonia.Diagnostics.Controls"
+        x:ClassModifier="internal">
 
     <Styles.Resources>
         <SolidColorBrush x:Key="HighlightBorderBrush" Color="CornflowerBlue" />
diff --git a/src/Avalonia.FreeDesktop/Avalonia.FreeDesktop.csproj b/src/Avalonia.FreeDesktop/Avalonia.FreeDesktop.csproj
index 31b65dcc02..779c41757a 100644
--- a/src/Avalonia.FreeDesktop/Avalonia.FreeDesktop.csproj
+++ b/src/Avalonia.FreeDesktop/Avalonia.FreeDesktop.csproj
@@ -13,7 +13,7 @@
 
   <ItemGroup>
     <PackageReference Include="Tmds.DBus.Protocol" Version="0.15.0" />
-    <PackageReference Include="Tmds.DBus.SourceGenerator" Version="0.0.7" PrivateAssets="All" />
+    <PackageReference Include="Tmds.DBus.SourceGenerator" Version="0.0.8" PrivateAssets="All" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/src/Avalonia.FreeDesktop/DBusIme/DBusTextInputMethodBase.cs b/src/Avalonia.FreeDesktop/DBusIme/DBusTextInputMethodBase.cs
index d3c14f285d..936e856cf0 100644
--- a/src/Avalonia.FreeDesktop/DBusIme/DBusTextInputMethodBase.cs
+++ b/src/Avalonia.FreeDesktop/DBusIme/DBusTextInputMethodBase.cs
@@ -76,7 +76,10 @@ namespace Avalonia.FreeDesktop.DBusIme
         private async void OnNameChange(Exception? e, (string ServiceName, string? OldOwner, string? NewOwner) args)
         {
             if (e is not null)
+            {
+                Logger.TryGet(LogEventLevel.Error, LogArea.FreeDesktopPlatform)?.Log(this, $"OnNameChange failed: {e}");
                 return;
+            }
 
             if (args.NewOwner is not null && _currentName is null)
             {
diff --git a/src/Avalonia.FreeDesktop/DBusIme/Fcitx/FcitxX11TextInputMethod.cs b/src/Avalonia.FreeDesktop/DBusIme/Fcitx/FcitxX11TextInputMethod.cs
index 1cf3507cc2..2eca5a1fef 100644
--- a/src/Avalonia.FreeDesktop/DBusIme/Fcitx/FcitxX11TextInputMethod.cs
+++ b/src/Avalonia.FreeDesktop/DBusIme/Fcitx/FcitxX11TextInputMethod.cs
@@ -4,6 +4,7 @@ using System.Threading.Tasks;
 using Avalonia.Input;
 using Avalonia.Input.Raw;
 using Avalonia.Input.TextInput;
+using Avalonia.Logging;
 using Tmds.DBus.Protocol;
 using Tmds.DBus.SourceGenerator;
 
@@ -138,7 +139,10 @@ namespace Avalonia.FreeDesktop.DBusIme.Fcitx
         private void OnCommitString(Exception? e, string s)
         {
             if (e is not null)
+            {
+                Logger.TryGet(LogEventLevel.Error, LogArea.FreeDesktopPlatform)?.Log(this, $"OnCommitString failed: {e}");
                 return;
+            }
 
             FireCommit(s);
         }
diff --git a/src/Avalonia.FreeDesktop/DBusIme/IBus/IBusX11TextInputMethod.cs b/src/Avalonia.FreeDesktop/DBusIme/IBus/IBusX11TextInputMethod.cs
index 59e9ecd1cf..26fa971106 100644
--- a/src/Avalonia.FreeDesktop/DBusIme/IBus/IBusX11TextInputMethod.cs
+++ b/src/Avalonia.FreeDesktop/DBusIme/IBus/IBusX11TextInputMethod.cs
@@ -3,6 +3,7 @@ using System.Threading.Tasks;
 using Avalonia.Input;
 using Avalonia.Input.Raw;
 using Avalonia.Input.TextInput;
+using Avalonia.Logging;
 using Tmds.DBus.Protocol;
 using Tmds.DBus.SourceGenerator;
 
@@ -31,7 +32,10 @@ namespace Avalonia.FreeDesktop.DBusIme.IBus
         private void OnForwardKey(Exception? e, (uint keyval, uint keycode, uint state) k)
         {
             if (e is not null)
+            {
+                Logger.TryGet(LogEventLevel.Error, LogArea.FreeDesktopPlatform)?.Log(this, $"OnForwardKey failed: {e}");
                 return;
+            }
 
             var state = (IBusModifierMask)k.state;
             KeyModifiers mods = default;
@@ -54,7 +58,10 @@ namespace Avalonia.FreeDesktop.DBusIme.IBus
         private void OnCommitText(Exception? e, DBusVariantItem variantItem)
         {
             if (e is not null)
+            {
+                Logger.TryGet(LogEventLevel.Error, LogArea.FreeDesktopPlatform)?.Log(this, $"OnCommitText failed: {e}");
                 return;
+            }
 
             if (variantItem.Value is DBusStructItem { Count: >= 3 } structItem && structItem[2] is DBusStringItem stringItem)
                 FireCommit(stringItem.Value);
diff --git a/src/Avalonia.FreeDesktop/DBusSystemDialog.cs b/src/Avalonia.FreeDesktop/DBusSystemDialog.cs
index cd6f829d7a..f6964ab92a 100644
--- a/src/Avalonia.FreeDesktop/DBusSystemDialog.cs
+++ b/src/Avalonia.FreeDesktop/DBusSystemDialog.cs
@@ -2,6 +2,7 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Text;
 using System.Threading.Tasks;
 using Avalonia.Platform;
 using Avalonia.Platform.Storage;
@@ -66,8 +67,9 @@ namespace Avalonia.FreeDesktop
             using var disposable = await request.WatchResponseAsync((e, x) =>
             {
                 if (e is not null)
-                    return;
-                tsc.TrySetResult((x.results["uris"].Value as DBusArrayItem)?.Select(static y => (y as DBusStringItem)!.Value).ToArray());
+                    tsc.TrySetException(e);
+                else
+                    tsc.TrySetResult((x.results["uris"].Value as DBusArrayItem)?.Select(static y => (y as DBusStringItem)!.Value).ToArray());
             });
 
             var uris = await tsc.Task ?? Array.Empty<string>();
@@ -86,7 +88,7 @@ namespace Avalonia.FreeDesktop
             if (options.SuggestedFileName is { } currentName)
                 chooserOptions.Add("current_name", new DBusVariantItem("s", new DBusStringItem(currentName)));
             if (options.SuggestedStartLocation?.TryGetLocalPath()  is { } folderPath)
-                chooserOptions.Add("current_folder", new DBusVariantItem("s", new DBusStringItem(folderPath)));
+                chooserOptions.Add("current_folder", new DBusVariantItem("ay", new DBusArrayItem(DBusType.Byte, Encoding.UTF8.GetBytes(folderPath).Select(static x => new DBusByteItem(x)))));
 
             objectPath = await _fileChooser.SaveFileAsync(parentWindow, options.Title ?? string.Empty, chooserOptions);
             var request = new OrgFreedesktopPortalRequest(_connection, "org.freedesktop.portal.Desktop", objectPath);
@@ -94,8 +96,9 @@ namespace Avalonia.FreeDesktop
             using var disposable = await request.WatchResponseAsync((e, x) =>
             {
                 if (e is not null)
-                    return;
-                tsc.TrySetResult((x.results["uris"].Value as DBusArrayItem)?.Select(static y => (y as DBusStringItem)!.Value).ToArray());
+                    tsc.TrySetException(e);
+                else
+                    tsc.TrySetResult((x.results["uris"].Value as DBusArrayItem)?.Select(static y => (y as DBusStringItem)!.Value).ToArray());
             });
 
             var uris = await tsc.Task;
@@ -124,8 +127,9 @@ namespace Avalonia.FreeDesktop
             using var disposable = await request.WatchResponseAsync((e, x) =>
             {
                 if (e is not null)
-                    return;
-                tsc.TrySetResult((x.results["uris"].Value as DBusArrayItem)?.Select(static y => (y as DBusStringItem)!.Value).ToArray());
+                    tsc.TrySetException(e);
+                else
+                    tsc.TrySetResult((x.results["uris"].Value as DBusArrayItem)?.Select(static y => (y as DBusStringItem)!.Value).ToArray());
             });
 
             var uris = await tsc.Task ?? Array.Empty<string>();
diff --git a/src/Avalonia.FreeDesktop/DBusTrayIconImpl.cs b/src/Avalonia.FreeDesktop/DBusTrayIconImpl.cs
index 43ae48341c..9abf4f97a7 100644
--- a/src/Avalonia.FreeDesktop/DBusTrayIconImpl.cs
+++ b/src/Avalonia.FreeDesktop/DBusTrayIconImpl.cs
@@ -4,7 +4,6 @@ using System.Threading.Tasks;
 using Avalonia.Controls.Platform;
 using Avalonia.Logging;
 using Avalonia.Platform;
-using Avalonia.Threading;
 using Tmds.DBus.Protocol;
 using Tmds.DBus.SourceGenerator;
 
@@ -57,15 +56,6 @@ namespace Avalonia.FreeDesktop
             WatchAsync();
         }
 
-        private void InitializeSNWService()
-        {
-            if (_connection is null || _isDisposed)
-                return;
-
-            _statusNotifierWatcher = new OrgKdeStatusNotifierWatcher(_connection, "org.kde.StatusNotifierWatcher", "/StatusNotifierWatcher");
-            _serviceConnected = true;
-        }
-
         private async void WatchAsync()
         {
             try
@@ -84,13 +74,13 @@ namespace Avalonia.FreeDesktop
 
         private void OnNameChange(string? newOwner)
         {
-            if (_isDisposed)
+            if (_isDisposed || _connection is null)
                 return;
 
             if (!_serviceConnected & newOwner is not null)
             {
                 _serviceConnected = true;
-                InitializeSNWService();
+                _statusNotifierWatcher = new OrgKdeStatusNotifierWatcher(_connection, "org.kde.StatusNotifierWatcher", "/StatusNotifierWatcher");
 
                 DestroyTrayIcon();
 
@@ -182,8 +172,11 @@ namespace Avalonia.FreeDesktop
 
         public void SetIsVisible(bool visible)
         {
-            if (_isDisposed)
+            if (_isDisposed || !_serviceConnected)
+            {
+                _isVisible = visible;
                 return;
+            }
 
             switch (visible)
             {
diff --git a/src/Avalonia.Native/AvaloniaNativePlatform.cs b/src/Avalonia.Native/AvaloniaNativePlatform.cs
index e6a103f6b9..c471cf91d2 100644
--- a/src/Avalonia.Native/AvaloniaNativePlatform.cs
+++ b/src/Avalonia.Native/AvaloniaNativePlatform.cs
@@ -113,10 +113,7 @@ namespace Avalonia.Native
                 .Bind<IPlatformDragSource>().ToConstant(new AvaloniaNativeDragSource(_factory))
                 .Bind<IPlatformLifetimeEventsImpl>().ToConstant(applicationPlatform)
                 .Bind<INativeApplicationCommands>().ToConstant(new MacOSNativeMenuCommands(_factory.CreateApplicationCommands()));
-
-            var renderLoop = new RenderLoop();
-            AvaloniaLocator.CurrentMutable.Bind<IRenderLoop>().ToConstant(renderLoop);
-
+            
             var hotkeys = AvaloniaLocator.Current.GetService<PlatformHotkeyConfiguration>();
             if (hotkeys is not null)
             {
@@ -141,7 +138,7 @@ namespace Avalonia.Native
                 }
             }
             
-            Compositor = new Compositor(renderLoop, _platformGl);
+            Compositor = new Compositor(_platformGl, true);
         }
 
         public ITrayIconImpl CreateTrayIcon()
diff --git a/src/Avalonia.Native/WindowImplBase.cs b/src/Avalonia.Native/WindowImplBase.cs
index b802b1db71..760816643e 100644
--- a/src/Avalonia.Native/WindowImplBase.cs
+++ b/src/Avalonia.Native/WindowImplBase.cs
@@ -65,6 +65,7 @@ namespace Avalonia.Native
         private NativeControlHostImpl _nativeControlHost;
         private IStorageProvider _storageProvider;
         private PlatformBehaviorInhibition _platformBehaviorInhibition;
+        private WindowTransparencyLevel _transparencyLevel = WindowTransparencyLevel.None;
 
         internal WindowBaseImpl(IAvaloniaNativeFactory factory, AvaloniaNativePlatformOptions opts,
             AvaloniaNativeGlPlatformGraphics glFeature)
@@ -200,7 +201,7 @@ namespace Avalonia.Native
 
             void IAvnWindowBaseEvents.Paint()
             {
-                Dispatcher.UIThread.RunJobs(DispatcherPriority.Render);
+                Dispatcher.UIThread.RunJobs(DispatcherPriority.UiThreadRender);
                 var s = _parent.ClientSize;
                 _parent.Paint?.Invoke(new Rect(0, 0, s.Width, s.Height));
             }
@@ -243,7 +244,7 @@ namespace Avalonia.Native
 
             void IAvnWindowBaseEvents.RunRenderPriorityJobs()
             {
-                Dispatcher.UIThread.RunJobs(DispatcherPriority.Render);
+                Dispatcher.UIThread.RunJobs(DispatcherPriority.UiThreadRender);
             }
             
             void IAvnWindowBaseEvents.LostFocus()
@@ -365,13 +366,7 @@ namespace Avalonia.Native
             _native?.Resize(clientSize.Width, clientSize.Height, (AvnPlatformResizeReason)reason);
         }
 
-        public IRenderer CreateRenderer(IRenderRoot root)
-        {
-            return new CompositingRenderer(root, AvaloniaNativePlatform.Compositor, () => Surfaces)
-            {
-                RenderOnlyOnRenderThread = false
-            };
-        }
+        public Compositor Compositor => AvaloniaNativePlatform.Compositor;
 
         public virtual void Dispose()
         {
@@ -485,26 +480,47 @@ namespace Avalonia.Native
             _native?.BeginDragAndDropOperation(effects, point, clipboard, callback, sourceHandle);
         }
 
-        public void SetTransparencyLevelHint(WindowTransparencyLevel transparencyLevel) 
+        public void SetTransparencyLevelHint(IReadOnlyList<WindowTransparencyLevel> transparencyLevels) 
         {
-            if (TransparencyLevel != transparencyLevel)
+            foreach (var level in transparencyLevels)
             {
-                if (transparencyLevel > WindowTransparencyLevel.Transparent)
-                    transparencyLevel = WindowTransparencyLevel.AcrylicBlur;
+                AvnWindowTransparencyMode? mode = null;
 
-                TransparencyLevel = transparencyLevel;
+                if (level == WindowTransparencyLevel.None)
+                    mode = AvnWindowTransparencyMode.Opaque;
+                if (level == WindowTransparencyLevel.Transparent)
+                    mode = AvnWindowTransparencyMode.Transparent;
+                else if (level == WindowTransparencyLevel.AcrylicBlur)
+                    mode = AvnWindowTransparencyMode.Blur;
 
-                _native.SetTransparencyMode(transparencyLevel == WindowTransparencyLevel.None
-                    ? AvnWindowTransparencyMode.Opaque 
-                    : transparencyLevel == WindowTransparencyLevel.Transparent 
-                        ? AvnWindowTransparencyMode.Transparent
-                        : AvnWindowTransparencyMode.Blur);
+                if (mode.HasValue && level != TransparencyLevel)
+                {
+                    _native?.SetTransparencyMode(mode.Value);
+                    TransparencyLevel = level;
+                    return;
+                }
+            }
 
-                TransparencyLevelChanged?.Invoke(TransparencyLevel);
+            // If we get here, we didn't find a supported level. Use the default of None.
+            if (TransparencyLevel != WindowTransparencyLevel.None)
+            {
+                _native?.SetTransparencyMode(AvnWindowTransparencyMode.Opaque);
+                TransparencyLevel = WindowTransparencyLevel.None;
             }
         }
 
-        public WindowTransparencyLevel TransparencyLevel { get; private set; } = WindowTransparencyLevel.None;
+        public WindowTransparencyLevel TransparencyLevel
+        {
+            get => _transparencyLevel;
+            private set
+            {
+                if (_transparencyLevel != value)
+                {
+                    _transparencyLevel = value;
+                    TransparencyLevelChanged?.Invoke(value);
+                }
+            }
+        }
 
         public void SetFrameThemeVariant(PlatformThemeVariant themeVariant)
         {
diff --git a/src/Avalonia.Themes.Fluent/Accents/BaseColorsPalette.xaml b/src/Avalonia.Themes.Fluent/Accents/BaseColorsPalette.xaml
index 362d543646..620add9045 100644
--- a/src/Avalonia.Themes.Fluent/Accents/BaseColorsPalette.xaml
+++ b/src/Avalonia.Themes.Fluent/Accents/BaseColorsPalette.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <!-- https://docs.microsoft.com/en-us/previous-versions/windows/apps/dn518235(v=win.10)?redirectedfrom=MSDN -->
   <ResourceDictionary.ThemeDictionaries>
     <ResourceDictionary x:Key="Default">
diff --git a/src/Avalonia.Themes.Fluent/Accents/BaseResources.xaml b/src/Avalonia.Themes.Fluent/Accents/BaseResources.xaml
index 517a80fd7e..6f12f1d306 100644
--- a/src/Avalonia.Themes.Fluent/Accents/BaseResources.xaml
+++ b/src/Avalonia.Themes.Fluent/Accents/BaseResources.xaml
@@ -1,7 +1,8 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:sys="using:System"
-                    xmlns:converters="using:Avalonia.Controls.Converters">
+                    xmlns:converters="using:Avalonia.Controls.Converters"
+                    x:ClassModifier="internal">
   <FontFamily x:Key="ContentControlThemeFontFamily">fonts:Inter#Inter, $Default</FontFamily>
   <sys:Double x:Key="ControlContentThemeFontSize">14</sys:Double>
 
diff --git a/src/Avalonia.Themes.Fluent/Accents/FluentControlResources.xaml b/src/Avalonia.Themes.Fluent/Accents/FluentControlResources.xaml
index 61a74f26a4..397f7ec431 100644
--- a/src/Avalonia.Themes.Fluent/Accents/FluentControlResources.xaml
+++ b/src/Avalonia.Themes.Fluent/Accents/FluentControlResources.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ResourceDictionary.ThemeDictionaries>
     <ResourceDictionary x:Key="Default">
       <!-- Resources for Button.xaml -->
diff --git a/src/Avalonia.Themes.Fluent/Avalonia.Themes.Fluent.csproj b/src/Avalonia.Themes.Fluent/Avalonia.Themes.Fluent.csproj
index e63a0c9c26..660661fc94 100644
--- a/src/Avalonia.Themes.Fluent/Avalonia.Themes.Fluent.csproj
+++ b/src/Avalonia.Themes.Fluent/Avalonia.Themes.Fluent.csproj
@@ -1,8 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>net6.0;netstandard2.0</TargetFrameworks>
-    <!-- NativeMenuBar uses ReflectionBinding -->
-    <NoWarn>$(NoWarn);IL2026</NoWarn>
   </PropertyGroup>
   <ItemGroup>
     <ProjectReference Include="..\Avalonia.Base\Avalonia.Base.csproj" />
diff --git a/src/Avalonia.Themes.Fluent/Controls/AdornerLayer.xaml b/src/Avalonia.Themes.Fluent/Controls/AdornerLayer.xaml
index c4b91b4822..fefa1ea055 100644
--- a/src/Avalonia.Themes.Fluent/Controls/AdornerLayer.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/AdornerLayer.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Thickness x:Key="SystemControlFocusVisualMargin">0</Thickness>
   <Thickness x:Key="SystemControlFocusVisualPrimaryThickness">2</Thickness>
   <Thickness x:Key="SystemControlFocusVisualSecondaryThickness">1</Thickness>
diff --git a/src/Avalonia.Themes.Fluent/Controls/AutoCompleteBox.xaml b/src/Avalonia.Themes.Fluent/Controls/AutoCompleteBox.xaml
index 2113ae4cb0..228aeaad17 100644
--- a/src/Avalonia.Themes.Fluent/Controls/AutoCompleteBox.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/AutoCompleteBox.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:generic="using:System.Collections.Generic">
+                    xmlns:generic="using:System.Collections.Generic"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <AutoCompleteBox Width="200">
diff --git a/src/Avalonia.Themes.Fluent/Controls/Button.xaml b/src/Avalonia.Themes.Fluent/Controls/Button.xaml
index 126f2c22e0..6c6ca967e7 100644
--- a/src/Avalonia.Themes.Fluent/Controls/Button.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/Button.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/ButtonSpinner.xaml b/src/Avalonia.Themes.Fluent/Controls/ButtonSpinner.xaml
index 3ce4730698..095e801d0c 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ButtonSpinner.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ButtonSpinner.xaml
@@ -1,7 +1,8 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:sys="using:System"
-                    xmlns:converters="using:Avalonia.Controls.Converters">
+                    xmlns:converters="using:Avalonia.Controls.Converters"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/Calendar.xaml b/src/Avalonia.Themes.Fluent/Controls/Calendar.xaml
index 9c66ea9b84..2f4a444529 100644
--- a/src/Avalonia.Themes.Fluent/Controls/Calendar.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/Calendar.xaml
@@ -6,7 +6,8 @@
 -->
 
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <Calendar />
diff --git a/src/Avalonia.Themes.Fluent/Controls/CalendarButton.xaml b/src/Avalonia.Themes.Fluent/Controls/CalendarButton.xaml
index 76b51ca819..206973b7ee 100644
--- a/src/Avalonia.Themes.Fluent/Controls/CalendarButton.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/CalendarButton.xaml
@@ -5,7 +5,8 @@
 // All other rights reserved.
 -->
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/CalendarDatePicker.xaml b/src/Avalonia.Themes.Fluent/Controls/CalendarDatePicker.xaml
index 2a3496b648..4739a5b9c5 100644
--- a/src/Avalonia.Themes.Fluent/Controls/CalendarDatePicker.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/CalendarDatePicker.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:sys="using:System">
+                    xmlns:sys="using:System"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Margin="20, 20, 20, 200">
       <CalendarDatePicker Width="200" VerticalContentAlignment="Center" HorizontalContentAlignment="Center" />
diff --git a/src/Avalonia.Themes.Fluent/Controls/CalendarDayButton.xaml b/src/Avalonia.Themes.Fluent/Controls/CalendarDayButton.xaml
index 6a57cfacd0..904a234ada 100644
--- a/src/Avalonia.Themes.Fluent/Controls/CalendarDayButton.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/CalendarDayButton.xaml
@@ -5,7 +5,8 @@
 // All other rights reserved.
 -->
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/CalendarItem.xaml b/src/Avalonia.Themes.Fluent/Controls/CalendarItem.xaml
index 7276742e7d..3bbef81695 100644
--- a/src/Avalonia.Themes.Fluent/Controls/CalendarItem.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/CalendarItem.xaml
@@ -6,7 +6,8 @@
 -->
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:sys="using:System">
+        xmlns:sys="using:System"
+        x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <Calendar DisplayDate="2000-01-01">
diff --git a/src/Avalonia.Themes.Fluent/Controls/CaptionButtons.xaml b/src/Avalonia.Themes.Fluent/Controls/CaptionButtons.xaml
index 0180c3f395..41d74c6063 100644
--- a/src/Avalonia.Themes.Fluent/Controls/CaptionButtons.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/CaptionButtons.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/Carousel.xaml b/src/Avalonia.Themes.Fluent/Controls/Carousel.xaml
index 91e331693e..b94ef9b5d9 100644
--- a/src/Avalonia.Themes.Fluent/Controls/Carousel.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/Carousel.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type Carousel}" TargetType="Carousel">
     <Setter Property="Template">
       <ControlTemplate>
diff --git a/src/Avalonia.Themes.Fluent/Controls/CheckBox.xaml b/src/Avalonia.Themes.Fluent/Controls/CheckBox.xaml
index 28f8649e2d..fc0a8c7c66 100644
--- a/src/Avalonia.Themes.Fluent/Controls/CheckBox.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/CheckBox.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/ComboBox.xaml b/src/Avalonia.Themes.Fluent/Controls/ComboBox.xaml
index bc36ad987e..18bf01ece7 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ComboBox.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ComboBox.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:sys="using:System">
+                    xmlns:sys="using:System"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="10">
diff --git a/src/Avalonia.Themes.Fluent/Controls/ComboBoxItem.xaml b/src/Avalonia.Themes.Fluent/Controls/ComboBoxItem.xaml
index 581cbaf80a..ea55770a51 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ComboBoxItem.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ComboBoxItem.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <Border Background="{DynamicResource ComboBoxDropDownBackground}" BorderBrush="{DynamicResource ComboBoxDropDownBorderBrush}" BorderThickness="{DynamicResource ComboBoxDropdownBorderThickness}" Margin="0,-1,0,-1" Padding="{DynamicResource ComboBoxDropdownBorderPadding}" CornerRadius="{DynamicResource OverlayCornerRadius}">
diff --git a/src/Avalonia.Themes.Fluent/Controls/ContentControl.xaml b/src/Avalonia.Themes.Fluent/Controls/ContentControl.xaml
index 4caf156366..f277c6f9ae 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ContentControl.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ContentControl.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ContentControl}" TargetType="ContentControl">
     <Setter Property="Template">
       <ControlTemplate>
diff --git a/src/Avalonia.Themes.Fluent/Controls/ContextMenu.xaml b/src/Avalonia.Themes.Fluent/Controls/ContextMenu.xaml
index f6900f785f..c8e2873eb6 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ContextMenu.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ContextMenu.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Background="{DynamicResource SystemAccentColor}"
             Margin="16"
diff --git a/src/Avalonia.Themes.Fluent/Controls/DataValidationErrors.xaml b/src/Avalonia.Themes.Fluent/Controls/DataValidationErrors.xaml
index 984a523471..94f1d3cdda 100644
--- a/src/Avalonia.Themes.Fluent/Controls/DataValidationErrors.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/DataValidationErrors.xaml
@@ -1,7 +1,8 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:sys="using:System"
-                    xmlns:collections="using:System.Collections">
+                    xmlns:collections="using:System.Collections"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/DatePicker.xaml b/src/Avalonia.Themes.Fluent/Controls/DatePicker.xaml
index e71e733eff..58f181bd23 100644
--- a/src/Avalonia.Themes.Fluent/Controls/DatePicker.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/DatePicker.xaml
@@ -7,7 +7,8 @@
 
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:sys="using:System">
+        xmlns:sys="using:System"
+        x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20" Height="500">
       <StackPanel Spacing="20" VerticalAlignment="Center">
diff --git a/src/Avalonia.Themes.Fluent/Controls/DateTimePickerShared.xaml b/src/Avalonia.Themes.Fluent/Controls/DateTimePickerShared.xaml
index 9d21e6e758..9384eff8f4 100644
--- a/src/Avalonia.Themes.Fluent/Controls/DateTimePickerShared.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/DateTimePickerShared.xaml
@@ -6,7 +6,8 @@
 -->
 
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20" Width="200">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/DropDownButton.xaml b/src/Avalonia.Themes.Fluent/Controls/DropDownButton.xaml
index 421ba0bb18..438ad6cf18 100644
--- a/src/Avalonia.Themes.Fluent/Controls/DropDownButton.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/DropDownButton.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
     <Design.PreviewWith>
       <Border Padding="20">
         <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/EmbeddableControlRoot.xaml b/src/Avalonia.Themes.Fluent/Controls/EmbeddableControlRoot.xaml
index ee51ef8085..1fc931db36 100644
--- a/src/Avalonia.Themes.Fluent/Controls/EmbeddableControlRoot.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/EmbeddableControlRoot.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type EmbeddableControlRoot}" TargetType="EmbeddableControlRoot">
     <Setter Property="Foreground" Value="{DynamicResource SystemControlForegroundBaseHighBrush}"/>
     <Setter Property="Background" Value="{DynamicResource SystemRegionBrush}"/>
diff --git a/src/Avalonia.Themes.Fluent/Controls/Expander.xaml b/src/Avalonia.Themes.Fluent/Controls/Expander.xaml
index 37e9b71185..adaecc71ab 100644
--- a/src/Avalonia.Themes.Fluent/Controls/Expander.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/Expander.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
 
   <Design.PreviewWith>
     <Border Padding="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/FluentControls.xaml b/src/Avalonia.Themes.Fluent/Controls/FluentControls.xaml
index 31b0a01b21..deb7d39a89 100644
--- a/src/Avalonia.Themes.Fluent/Controls/FluentControls.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/FluentControls.xaml
@@ -1,6 +1,7 @@
 <Styles
     xmlns="https://github.com/avaloniaui"
-    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    x:ClassModifier="internal">
     <Styles.Resources>
         <ResourceDictionary>
             <ResourceDictionary.MergedDictionaries>
diff --git a/src/Avalonia.Themes.Fluent/Controls/FlyoutPresenter.xaml b/src/Avalonia.Themes.Fluent/Controls/FlyoutPresenter.xaml
index 2dca5b0770..e8c9ed9b2a 100644
--- a/src/Avalonia.Themes.Fluent/Controls/FlyoutPresenter.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/FlyoutPresenter.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Thickness x:Key="FlyoutBorderThemeThickness">1</Thickness>
   <ControlTheme x:Key="{x:Type FlyoutPresenter}" TargetType="FlyoutPresenter">
     <Setter Property="HorizontalContentAlignment" Value="Stretch" />
diff --git a/src/Avalonia.Themes.Fluent/Controls/GridSplitter.xaml b/src/Avalonia.Themes.Fluent/Controls/GridSplitter.xaml
index ca57eccd13..fc08d6b0b6 100644
--- a/src/Avalonia.Themes.Fluent/Controls/GridSplitter.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/GridSplitter.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
     <ControlTheme x:Key="{x:Type GridSplitter}" TargetType="GridSplitter">
       <Setter Property="Focusable" Value="True" />
       <Setter Property="MinWidth" Value="6" />
diff --git a/src/Avalonia.Themes.Fluent/Controls/ItemsControl.xaml b/src/Avalonia.Themes.Fluent/Controls/ItemsControl.xaml
index 19a29b9466..91f9536847 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ItemsControl.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ItemsControl.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ItemsControl}" TargetType="ItemsControl">
     <Setter Property="Template">
       <ControlTemplate>
diff --git a/src/Avalonia.Themes.Fluent/Controls/Label.xaml b/src/Avalonia.Themes.Fluent/Controls/Label.xaml
index ff6909ee87..237da0bfa3 100644
--- a/src/Avalonia.Themes.Fluent/Controls/Label.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/Label.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
 
   <ControlTheme x:Key="{x:Type Label}" TargetType="Label">
     <Setter Property="Padding" Value="3"/>
diff --git a/src/Avalonia.Themes.Fluent/Controls/ListBox.xaml b/src/Avalonia.Themes.Fluent/Controls/ListBox.xaml
index 05bbbe9558..2dde18a523 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ListBox.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ListBox.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <ListBox>
diff --git a/src/Avalonia.Themes.Fluent/Controls/ListBoxItem.xaml b/src/Avalonia.Themes.Fluent/Controls/ListBoxItem.xaml
index fc1d0c5ff1..4e74406c92 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ListBoxItem.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ListBoxItem.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="0">
       <ListBox>
diff --git a/src/Avalonia.Themes.Fluent/Controls/ManagedFileChooser.xaml b/src/Avalonia.Themes.Fluent/Controls/ManagedFileChooser.xaml
index b3453569a4..374daa7ab5 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ManagedFileChooser.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ManagedFileChooser.xaml
@@ -1,7 +1,8 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:dialogs="using:Avalonia.Dialogs"
-        xmlns:internal="using:Avalonia.Dialogs.Internal">
+        xmlns:internal="using:Avalonia.Dialogs.Internal"
+        x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20" Width="800" Height="500">
       <dialogs:ManagedFileChooser/>
@@ -179,8 +180,8 @@
               </DockPanel>
               <CheckBox IsChecked="{Binding ShowHiddenFiles}" Content="Show hidden files" DockPanel.Dock="Left"/>
               <UniformGrid x:Name="Finalize" HorizontalAlignment="Right" Rows="1">
-                <Button Command="{Binding Ok}">OK</Button>
-                <Button Command="{Binding Cancel}">Cancel</Button>
+                <Button Command="{Binding Ok}" MinWidth="80">OK</Button>
+                <Button Command="{Binding Cancel}" MinWidth="80">Cancel</Button>
               </UniformGrid>
             </DockPanel>
           </DockPanel>
@@ -189,7 +190,6 @@
             <Grid DockPanel.Dock="Top" Margin="15 5 0 0" HorizontalAlignment="Stretch">
               <Grid.ColumnDefinitions>
                 <ColumnDefinition Width="20" SharedSizeGroup="Icon" />
-                <ColumnDefinition Width="16" SharedSizeGroup="Splitter"  />
                 <ColumnDefinition Width="275" SharedSizeGroup="Name" />
                 <ColumnDefinition Width="16" SharedSizeGroup="Splitter" />
                 <ColumnDefinition Width="200" SharedSizeGroup="Modified" />
@@ -197,6 +197,7 @@
                 <ColumnDefinition Width="150" SharedSizeGroup="Type" />
                 <ColumnDefinition Width="16" SharedSizeGroup="Splitter" />
                 <ColumnDefinition Width="200" SharedSizeGroup="Size" />
+                <ColumnDefinition Width="16" SharedSizeGroup="Splitter" />
               </Grid.ColumnDefinitions>
               <Grid.Styles>
                 <Style Selector="GridSplitter">
@@ -210,14 +211,14 @@
                   </Setter>
                 </Style>
               </Grid.Styles>
-              <GridSplitter Grid.Column="1" />
-              <TextBlock Grid.Column="2" Text="Name" />
-              <GridSplitter Grid.Column="3" />
-              <TextBlock Grid.Column="4" Text="Date Modified" />
-              <GridSplitter Grid.Column="5" />
-              <TextBlock Grid.Column="6" Text="Type" />
-              <GridSplitter Grid.Column="7" />
-              <TextBlock Grid.Column="8" Text="Size" />
+              <TextBlock Grid.Column="1" Text="Name" />
+              <GridSplitter Grid.Column="2" />
+              <TextBlock Grid.Column="3" Text="Date Modified" />
+              <GridSplitter Grid.Column="4" />
+              <TextBlock Grid.Column="5" Text="Type" />
+              <GridSplitter Grid.Column="6" />
+              <TextBlock Grid.Column="7" Text="Size" />
+              <GridSplitter Grid.Column="8" />
             </Grid>
             <ListBox x:Name="PART_Files"
                 ItemsSource="{Binding Items}"
@@ -231,7 +232,6 @@
                   <Grid Background="Transparent">
                     <Grid.ColumnDefinitions>
                       <ColumnDefinition SharedSizeGroup="Icon" />
-                      <ColumnDefinition SharedSizeGroup="Splitter"  />
                       <ColumnDefinition SharedSizeGroup="Name" />
                       <ColumnDefinition SharedSizeGroup="Splitter" />
                       <ColumnDefinition SharedSizeGroup="Modified" />
@@ -239,16 +239,17 @@
                       <ColumnDefinition SharedSizeGroup="Type" />
                       <ColumnDefinition SharedSizeGroup="Splitter" />
                       <ColumnDefinition SharedSizeGroup="Size" />
+                      <ColumnDefinition SharedSizeGroup="Splitter" />
                     </Grid.ColumnDefinitions>
                     <Image Width="16" Height="16">
                       <Image.Source>
                         <DrawingImage Drawing="{Binding IconKey, Converter={StaticResource Icons}}"/>
                       </Image.Source>
                     </Image>
-                    <TextBlock Grid.Column="2" Text="{Binding DisplayName}"/>
-                    <TextBlock Grid.Column="4" Text="{Binding Modified}" />
-                    <TextBlock Grid.Column="6" Text="{Binding Type}" />
-                    <TextBlock Grid.Column="8">
+                    <TextBlock Grid.Column="1" Text="{Binding DisplayName}"/>
+                    <TextBlock Grid.Column="3" Text="{Binding Modified}" />
+                    <TextBlock Grid.Column="5" Text="{Binding Type}" />
+                    <TextBlock Grid.Column="7" HorizontalAlignment="Right">
                       <TextBlock.Text>
                         <Binding Path="Size">
                           <Binding.Converter>
diff --git a/src/Avalonia.Themes.Fluent/Controls/Menu.xaml b/src/Avalonia.Themes.Fluent/Controls/Menu.xaml
index e6bbbde632..c1640efa8c 100644
--- a/src/Avalonia.Themes.Fluent/Controls/Menu.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/Menu.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <Menu>
diff --git a/src/Avalonia.Themes.Fluent/Controls/MenuFlyoutPresenter.xaml b/src/Avalonia.Themes.Fluent/Controls/MenuFlyoutPresenter.xaml
index b1f44cc70d..b5dff7b59d 100644
--- a/src/Avalonia.Themes.Fluent/Controls/MenuFlyoutPresenter.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/MenuFlyoutPresenter.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type MenuFlyoutPresenter}" TargetType="MenuFlyoutPresenter">
     <Setter Property="Background" Value="{DynamicResource MenuFlyoutPresenterBackground}" />
     <Setter Property="BorderBrush" Value="{DynamicResource MenuFlyoutPresenterBorderBrush}" />
diff --git a/src/Avalonia.Themes.Fluent/Controls/MenuItem.xaml b/src/Avalonia.Themes.Fluent/Controls/MenuItem.xaml
index c7ffdd3418..8a2d76b940 100644
--- a/src/Avalonia.Themes.Fluent/Controls/MenuItem.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/MenuItem.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:conv="using:Avalonia.Controls.Converters">
+                    xmlns:conv="using:Avalonia.Controls.Converters"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20" Width="320">
       <StackPanel Spacing="20" HorizontalAlignment="Left">
diff --git a/src/Avalonia.Themes.Fluent/Controls/MenuScrollViewer.xaml b/src/Avalonia.Themes.Fluent/Controls/MenuScrollViewer.xaml
index adca099a10..9dd65b1349 100644
--- a/src/Avalonia.Themes.Fluent/Controls/MenuScrollViewer.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/MenuScrollViewer.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:converters="using:Avalonia.Controls.Converters">
+                    xmlns:converters="using:Avalonia.Controls.Converters"
+                    x:ClassModifier="internal">
 
   <Design.PreviewWith>
     <ScrollViewer Theme="{DynamicResource FluentMenuScrollViewer}" Width="200" Height="200">
diff --git a/src/Avalonia.Themes.Fluent/Controls/NativeMenuBar.xaml b/src/Avalonia.Themes.Fluent/Controls/NativeMenuBar.xaml
index 515a5a730b..3e28ac3ddd 100644
--- a/src/Avalonia.Themes.Fluent/Controls/NativeMenuBar.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/NativeMenuBar.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:local="using:Avalonia.Themes.Fluent">
+                    xmlns:local="using:Avalonia.Themes.Fluent"
+                    x:ClassModifier="internal">
   <local:IBitmapToImageConverter x:Key="AvaloniaThemesFluentNativeMenuBarIBitmapToImageConverter"/>
   <ControlTheme x:Key="{x:Type NativeMenuBar}" TargetType="NativeMenuBar">
     <Setter Property="Template">
diff --git a/src/Avalonia.Themes.Fluent/Controls/NotificationCard.xaml b/src/Avalonia.Themes.Fluent/Controls/NotificationCard.xaml
index 51dcdd42e3..52e7280c95 100644
--- a/src/Avalonia.Themes.Fluent/Controls/NotificationCard.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/NotificationCard.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="0" Background="White">
       <NotificationCard Content="Testing" />
diff --git a/src/Avalonia.Themes.Fluent/Controls/NumericUpDown.xaml b/src/Avalonia.Themes.Fluent/Controls/NumericUpDown.xaml
index 872367c6da..1f84ee664c 100644
--- a/src/Avalonia.Themes.Fluent/Controls/NumericUpDown.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/NumericUpDown.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/OverlayPopupHost.xaml b/src/Avalonia.Themes.Fluent/Controls/OverlayPopupHost.xaml
index 28d8fb508c..1316a5bd65 100644
--- a/src/Avalonia.Themes.Fluent/Controls/OverlayPopupHost.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/OverlayPopupHost.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type OverlayPopupHost}" TargetType="OverlayPopupHost">
     <Setter Property="Foreground" Value="{DynamicResource SystemControlForegroundBaseHighBrush}"/>
     <Setter Property="FontSize" Value="{DynamicResource ControlContentThemeFontSize}"/>
diff --git a/src/Avalonia.Themes.Fluent/Controls/PathIcon.xaml b/src/Avalonia.Themes.Fluent/Controls/PathIcon.xaml
index 5584eb3ab9..2a817ccfcb 100644
--- a/src/Avalonia.Themes.Fluent/Controls/PathIcon.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/PathIcon.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <StackPanel>
       <StackPanel.Resources>
diff --git a/src/Avalonia.Themes.Fluent/Controls/PopupRoot.xaml b/src/Avalonia.Themes.Fluent/Controls/PopupRoot.xaml
index 5a924830b1..910c5f8d8c 100644
--- a/src/Avalonia.Themes.Fluent/Controls/PopupRoot.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/PopupRoot.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type PopupRoot}" TargetType="PopupRoot">
     <Setter Property="Background" Value="{x:Null}" />
     <Setter Property="TransparencyLevelHint" Value="Transparent" />
diff --git a/src/Avalonia.Themes.Fluent/Controls/ProgressBar.xaml b/src/Avalonia.Themes.Fluent/Controls/ProgressBar.xaml
index 64a598e359..adb8551ec3 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ProgressBar.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ProgressBar.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:converters="using:Avalonia.Controls.Converters">
+                    xmlns:converters="using:Avalonia.Controls.Converters"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Orientation="Horizontal" Spacing="10">
diff --git a/src/Avalonia.Themes.Fluent/Controls/RadioButton.xaml b/src/Avalonia.Themes.Fluent/Controls/RadioButton.xaml
index a1c4ba4f2d..39f89788bb 100644
--- a/src/Avalonia.Themes.Fluent/Controls/RadioButton.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/RadioButton.xaml
@@ -1,4 +1,5 @@
-<ResourceDictionary xmlns="https://github.com/avaloniaui" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+<ResourceDictionary xmlns="https://github.com/avaloniaui" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="10">
diff --git a/src/Avalonia.Themes.Fluent/Controls/RefreshContainer.xaml b/src/Avalonia.Themes.Fluent/Controls/RefreshContainer.xaml
index 8e29e6208f..b030acca30 100644
--- a/src/Avalonia.Themes.Fluent/Controls/RefreshContainer.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/RefreshContainer.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type RefreshContainer}"
                 TargetType="RefreshContainer">
     <Setter Property="Template">
diff --git a/src/Avalonia.Themes.Fluent/Controls/RefreshVisualizer.xaml b/src/Avalonia.Themes.Fluent/Controls/RefreshVisualizer.xaml
index 4e76bee9f5..a9ca8a0a5c 100644
--- a/src/Avalonia.Themes.Fluent/Controls/RefreshVisualizer.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/RefreshVisualizer.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type RefreshVisualizer}"
                 TargetType="RefreshVisualizer">
     <Setter Property="IsTabStop" Value="False"/>
diff --git a/src/Avalonia.Themes.Fluent/Controls/RepeatButton.xaml b/src/Avalonia.Themes.Fluent/Controls/RepeatButton.xaml
index fd04c85fed..b8a06f996a 100644
--- a/src/Avalonia.Themes.Fluent/Controls/RepeatButton.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/RepeatButton.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/ScrollBar.xaml b/src/Avalonia.Themes.Fluent/Controls/ScrollBar.xaml
index 4544fbe339..531f11a90b 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ScrollBar.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ScrollBar.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Orientation="Horizontal" Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/ScrollViewer.xaml b/src/Avalonia.Themes.Fluent/Controls/ScrollViewer.xaml
index 6218fe94ca..886a903a43 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ScrollViewer.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ScrollViewer.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary
   xmlns="https://github.com/avaloniaui"
-  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+  x:ClassModifier="internal">
   <Design.PreviewWith>
     <ScrollViewer Width="200" Height="200"
                   HorizontalScrollBarVisibility="Auto">
diff --git a/src/Avalonia.Themes.Fluent/Controls/SelectableTextBlock.xaml b/src/Avalonia.Themes.Fluent/Controls/SelectableTextBlock.xaml
index 2556f80ef6..b5daa65efc 100644
--- a/src/Avalonia.Themes.Fluent/Controls/SelectableTextBlock.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/SelectableTextBlock.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:ClassModifier="internal">
   <Design.PreviewWith>
     <SelectableTextBlock Text="Preview" />
   </Design.PreviewWith>
diff --git a/src/Avalonia.Themes.Fluent/Controls/Separator.xaml b/src/Avalonia.Themes.Fluent/Controls/Separator.xaml
index d13bffe5e1..3b4a111a58 100644
--- a/src/Avalonia.Themes.Fluent/Controls/Separator.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/Separator.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type Separator}" TargetType="Separator">
     <Setter Property="Background" Value="{DynamicResource SystemControlForegroundBaseMediumLowBrush}" />
     <Setter Property="Focusable" Value="False" />
diff --git a/src/Avalonia.Themes.Fluent/Controls/Slider.xaml b/src/Avalonia.Themes.Fluent/Controls/Slider.xaml
index 6e9e37643e..a4102a84d3 100644
--- a/src/Avalonia.Themes.Fluent/Controls/Slider.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/Slider.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:sys="using:System">
+                    xmlns:sys="using:System"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Margin="20" Width="400" Height="600">
       <DockPanel LastChildFill="True">
diff --git a/src/Avalonia.Themes.Fluent/Controls/SplitButton.xaml b/src/Avalonia.Themes.Fluent/Controls/SplitButton.xaml
index 1a7e72462a..98f8c8238e 100644
--- a/src/Avalonia.Themes.Fluent/Controls/SplitButton.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/SplitButton.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:converters="using:Avalonia.Controls.Converters">
+        xmlns:converters="using:Avalonia.Controls.Converters"
+        x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="60">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/SplitView.xaml b/src/Avalonia.Themes.Fluent/Controls/SplitView.xaml
index 9feb6c7fc6..aaf6ad7dbc 100644
--- a/src/Avalonia.Themes.Fluent/Controls/SplitView.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/SplitView.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:sys="using:System">
+        xmlns:sys="using:System"
+        x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Width="400" Height="400">
       <SplitView DisplayMode="Inline"
diff --git a/src/Avalonia.Themes.Fluent/Controls/TabControl.xaml b/src/Avalonia.Themes.Fluent/Controls/TabControl.xaml
index cd89443e1f..13b902a3a8 100644
--- a/src/Avalonia.Themes.Fluent/Controls/TabControl.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/TabControl.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Width="400">
       <TabControl>
diff --git a/src/Avalonia.Themes.Fluent/Controls/TabItem.xaml b/src/Avalonia.Themes.Fluent/Controls/TabItem.xaml
index b11ad4e03a..54eea85743 100644
--- a/src/Avalonia.Themes.Fluent/Controls/TabItem.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/TabItem.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary
     xmlns="https://github.com/avaloniaui"
-    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/TabStrip.xaml b/src/Avalonia.Themes.Fluent/Controls/TabStrip.xaml
index ead6fc41ab..ecaad94482 100644
--- a/src/Avalonia.Themes.Fluent/Controls/TabStrip.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/TabStrip.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <TabStrip>
diff --git a/src/Avalonia.Themes.Fluent/Controls/TabStripItem.xaml b/src/Avalonia.Themes.Fluent/Controls/TabStripItem.xaml
index d5440025ae..9c8584f7e5 100644
--- a/src/Avalonia.Themes.Fluent/Controls/TabStripItem.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/TabStripItem.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary
     xmlns="https://github.com/avaloniaui"
-    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/TextBox.xaml b/src/Avalonia.Themes.Fluent/Controls/TextBox.xaml
index 9449fcfb72..2c05ad6f64 100644
--- a/src/Avalonia.Themes.Fluent/Controls/TextBox.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/TextBox.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
@@ -133,7 +134,8 @@
                              IsVisible="False"
                              Text="{TemplateBinding Watermark}"
                              DockPanel.Dock="Top" />
-                  <ScrollViewer HorizontalScrollBarVisibility="{TemplateBinding (ScrollViewer.HorizontalScrollBarVisibility)}"
+                  <ScrollViewer Name="PART_ScrollViewer"
+                                HorizontalScrollBarVisibility="{TemplateBinding (ScrollViewer.HorizontalScrollBarVisibility)}"
                                 VerticalScrollBarVisibility="{TemplateBinding (ScrollViewer.VerticalScrollBarVisibility)}"
                                 IsScrollChainingEnabled="{TemplateBinding (ScrollViewer.IsScrollChainingEnabled)}"
                                 AllowAutoHide="{TemplateBinding (ScrollViewer.AllowAutoHide)}"
diff --git a/src/Avalonia.Themes.Fluent/Controls/ThemeVariantScope.xaml b/src/Avalonia.Themes.Fluent/Controls/ThemeVariantScope.xaml
index 21a5506b88..2e8715c9b9 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ThemeVariantScope.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ThemeVariantScope.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ThemeVariantScope}"
                 TargetType="ThemeVariantScope">
     <Setter Property="TextElement.Foreground" Value="{DynamicResource SystemControlForegroundBaseHighBrush}"/>
diff --git a/src/Avalonia.Themes.Fluent/Controls/TimePicker.xaml b/src/Avalonia.Themes.Fluent/Controls/TimePicker.xaml
index 39f7b0b224..38868f3cdf 100644
--- a/src/Avalonia.Themes.Fluent/Controls/TimePicker.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/TimePicker.xaml
@@ -7,7 +7,8 @@
 
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:sys="using:System">
+        xmlns:sys="using:System"
+        x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20" Height="500">
       <StackPanel Spacing="20" VerticalAlignment="Center">
diff --git a/src/Avalonia.Themes.Fluent/Controls/TitleBar.xaml b/src/Avalonia.Themes.Fluent/Controls/TitleBar.xaml
index 5730b19e78..2eff04218d 100644
--- a/src/Avalonia.Themes.Fluent/Controls/TitleBar.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/TitleBar.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
     <Design.PreviewWith>
       <Border Height="30" Width="300">
         <TitleBar Background="SkyBlue" Foreground="Black" />
diff --git a/src/Avalonia.Themes.Fluent/Controls/ToggleButton.xaml b/src/Avalonia.Themes.Fluent/Controls/ToggleButton.xaml
index da2021790a..1b54e6deaf 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ToggleButton.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ToggleButton.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/ToggleSwitch.xaml b/src/Avalonia.Themes.Fluent/Controls/ToggleSwitch.xaml
index c88839f7d2..47d7953096 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ToggleSwitch.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ToggleSwitch.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary
     xmlns="https://github.com/avaloniaui"
-    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    x:ClassModifier="internal">
   <Design.PreviewWith>
     <StackPanel Margin="20" Width="250" Spacing="24">
       <StackPanel Spacing="12" >
diff --git a/src/Avalonia.Themes.Fluent/Controls/ToolTip.xaml b/src/Avalonia.Themes.Fluent/Controls/ToolTip.xaml
index 8b086a8d10..b2fcfc7ddf 100644
--- a/src/Avalonia.Themes.Fluent/Controls/ToolTip.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/ToolTip.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:sys="using:System">
+                    xmlns:sys="using:System"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/TransitioningContentControl.xaml b/src/Avalonia.Themes.Fluent/Controls/TransitioningContentControl.xaml
index e53fc1aad4..2078322318 100644
--- a/src/Avalonia.Themes.Fluent/Controls/TransitioningContentControl.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/TransitioningContentControl.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type TransitioningContentControl}" TargetType="TransitioningContentControl">
     <Setter Property="Template">
       <ControlTemplate>
diff --git a/src/Avalonia.Themes.Fluent/Controls/TreeView.xaml b/src/Avalonia.Themes.Fluent/Controls/TreeView.xaml
index 241d3e2b74..0fdcaf39f8 100644
--- a/src/Avalonia.Themes.Fluent/Controls/TreeView.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/TreeView.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Fluent/Controls/TreeViewItem.xaml b/src/Avalonia.Themes.Fluent/Controls/TreeViewItem.xaml
index eff3920b12..c92774bc10 100644
--- a/src/Avalonia.Themes.Fluent/Controls/TreeViewItem.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/TreeViewItem.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:converters="using:Avalonia.Controls.Converters">
+        xmlns:converters="using:Avalonia.Controls.Converters"
+        x:ClassModifier="internal">
 
   <Design.PreviewWith>
     <Border Padding="20"
diff --git a/src/Avalonia.Themes.Fluent/Controls/UserControl.xaml b/src/Avalonia.Themes.Fluent/Controls/UserControl.xaml
index 7dc23f652a..bb75ec8bbc 100644
--- a/src/Avalonia.Themes.Fluent/Controls/UserControl.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/UserControl.xaml
@@ -1,6 +1,7 @@
 <Style xmlns="https://github.com/avaloniaui"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-       Selector=":is(UserControl)">
+       Selector=":is(UserControl)"
+       x:ClassModifier="internal">
   <Style.Resources>
     <ControlTheme x:Key="FluentUserControl" TargetType="UserControl">
       <Setter Property="Template">
diff --git a/src/Avalonia.Themes.Fluent/Controls/Window.xaml b/src/Avalonia.Themes.Fluent/Controls/Window.xaml
index 8db01fa4c8..52d16e7ada 100644
--- a/src/Avalonia.Themes.Fluent/Controls/Window.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/Window.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type Window}" TargetType="Window">
     <Setter Property="Background" Value="{DynamicResource SystemRegionBrush}"/>
     <Setter Property="TransparencyBackgroundFallback" Value="{DynamicResource SystemControlBackgroundAltHighBrush}" />
diff --git a/src/Avalonia.Themes.Fluent/Controls/WindowNotificationManager.xaml b/src/Avalonia.Themes.Fluent/Controls/WindowNotificationManager.xaml
index e4cd0b25a6..a62f4adfd6 100644
--- a/src/Avalonia.Themes.Fluent/Controls/WindowNotificationManager.xaml
+++ b/src/Avalonia.Themes.Fluent/Controls/WindowNotificationManager.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    x:DataType="WindowNotificationManager">
+                    x:DataType="WindowNotificationManager"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type WindowNotificationManager}" TargetType="WindowNotificationManager">
     <Setter Property="Margin" Value="0 0" />
     <Setter Property="Template">
diff --git a/src/Avalonia.Themes.Fluent/DensityStyles/Compact.xaml b/src/Avalonia.Themes.Fluent/DensityStyles/Compact.xaml
index b96671b778..d335e6f4b9 100644
--- a/src/Avalonia.Themes.Fluent/DensityStyles/Compact.xaml
+++ b/src/Avalonia.Themes.Fluent/DensityStyles/Compact.xaml
@@ -1,5 +1,6 @@
 <Styles xmlns="https://github.com/avaloniaui" 
-        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:ClassModifier="internal">
     <Style Selector="TextBlock" >
         <Setter Property="FontSize" Value="14" />
     </Style>
diff --git a/src/Avalonia.Themes.Fluent/FluentTheme.xaml b/src/Avalonia.Themes.Fluent/FluentTheme.xaml
index 0528c40c21..c84772aa61 100644
--- a/src/Avalonia.Themes.Fluent/FluentTheme.xaml
+++ b/src/Avalonia.Themes.Fluent/FluentTheme.xaml
@@ -2,7 +2,7 @@
         xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:fluent="using:Avalonia.Themes.Fluent"
-        xmlns:accents="clr-namespace:Avalonia.Themes.Fluent.Accents">
+        xmlns:accents="using:Avalonia.Themes.Fluent.Accents">
   <Styles.Resources>
     <ResourceDictionary>
       <ResourceDictionary.MergedDictionaries>
diff --git a/src/Avalonia.Themes.Simple/Accents/Base.xaml b/src/Avalonia.Themes.Simple/Accents/Base.xaml
index 0640fe9a4a..ca5c2e7d30 100644
--- a/src/Avalonia.Themes.Simple/Accents/Base.xaml
+++ b/src/Avalonia.Themes.Simple/Accents/Base.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:sys="using:System">
+                    xmlns:sys="using:System"
+                    x:ClassModifier="internal">
   <ResourceDictionary.ThemeDictionaries>
     <ResourceDictionary x:Key="Default">
       <Color x:Key="ThemeBackgroundColor">#FFFFFFFF</Color>
diff --git a/src/Avalonia.Themes.Simple/Avalonia.Themes.Simple.csproj b/src/Avalonia.Themes.Simple/Avalonia.Themes.Simple.csproj
index 03193599ed..39da9a747f 100644
--- a/src/Avalonia.Themes.Simple/Avalonia.Themes.Simple.csproj
+++ b/src/Avalonia.Themes.Simple/Avalonia.Themes.Simple.csproj
@@ -1,8 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>net6.0;netstandard2.0</TargetFrameworks>
-    <!-- NativeMenuBar uses ReflectionBinding -->
-    <NoWarn>$(NoWarn);IL2026</NoWarn>
   </PropertyGroup>
   <ItemGroup>
     <ProjectReference Include="..\Avalonia.Base\Avalonia.Base.csproj" />
diff --git a/src/Avalonia.Themes.Simple/Controls/AdornerLayer.xaml b/src/Avalonia.Themes.Simple/Controls/AdornerLayer.xaml
index 1f3acb07dc..165ab44fc8 100644
--- a/src/Avalonia.Themes.Simple/Controls/AdornerLayer.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/AdornerLayer.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type AdornerLayer}" TargetType="AdornerLayer">
     <Setter Property="DefaultFocusAdorner">
       <FocusAdornerTemplate>
diff --git a/src/Avalonia.Themes.Simple/Controls/AutoCompleteBox.xaml b/src/Avalonia.Themes.Simple/Controls/AutoCompleteBox.xaml
index 65dfaf982b..b861c5f3ea 100644
--- a/src/Avalonia.Themes.Simple/Controls/AutoCompleteBox.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/AutoCompleteBox.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type AutoCompleteBox}"
                 TargetType="AutoCompleteBox">
     <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/Button.xaml b/src/Avalonia.Themes.Simple/Controls/Button.xaml
index 9018677ab6..5599e49ae1 100644
--- a/src/Avalonia.Themes.Simple/Controls/Button.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/Button.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type Button}"
                 TargetType="Button">
     <Setter Property="Background" Value="{DynamicResource ThemeControlMidBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/ButtonSpinner.xaml b/src/Avalonia.Themes.Simple/Controls/ButtonSpinner.xaml
index 57d6eabea4..14472d601f 100644
--- a/src/Avalonia.Themes.Simple/Controls/ButtonSpinner.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ButtonSpinner.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
 
   <ControlTheme x:Key="SimpleButtonSpinnerRepeatButton"
                 BasedOn="{StaticResource {x:Type RepeatButton}}"
diff --git a/src/Avalonia.Themes.Simple/Controls/Calendar.xaml b/src/Avalonia.Themes.Simple/Controls/Calendar.xaml
index 08305319e1..e13f543a90 100644
--- a/src/Avalonia.Themes.Simple/Controls/Calendar.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/Calendar.xaml
@@ -6,7 +6,8 @@
 -->
 
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type Calendar}"
                 TargetType="Calendar">
     <!--<Setter Property="Focusable" Value="False" />-->
diff --git a/src/Avalonia.Themes.Simple/Controls/CalendarButton.xaml b/src/Avalonia.Themes.Simple/Controls/CalendarButton.xaml
index 9e13e1e996..1e06368d24 100644
--- a/src/Avalonia.Themes.Simple/Controls/CalendarButton.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/CalendarButton.xaml
@@ -6,7 +6,8 @@
 -->
 
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type CalendarButton}"
                 TargetType="CalendarButton">
     <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/CalendarDatePicker.xaml b/src/Avalonia.Themes.Simple/Controls/CalendarDatePicker.xaml
index a7c7b5f620..60759eebb1 100644
--- a/src/Avalonia.Themes.Simple/Controls/CalendarDatePicker.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/CalendarDatePicker.xaml
@@ -7,7 +7,8 @@
 
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:sys="using:System">
+                    xmlns:sys="using:System"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type CalendarDatePicker}"
                 TargetType="CalendarDatePicker">
     <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/CalendarDayButton.xaml b/src/Avalonia.Themes.Simple/Controls/CalendarDayButton.xaml
index 0973a3b752..e16b9f38ba 100644
--- a/src/Avalonia.Themes.Simple/Controls/CalendarDayButton.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/CalendarDayButton.xaml
@@ -6,7 +6,8 @@
 -->
 
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type CalendarDayButton}"
                 TargetType="CalendarDayButton">
     <Setter Property="Background" Value="{DynamicResource ThemeAccentBrush2}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/CalendarItem.xaml b/src/Avalonia.Themes.Simple/Controls/CalendarItem.xaml
index f022746bf5..e9e9299960 100644
--- a/src/Avalonia.Themes.Simple/Controls/CalendarItem.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/CalendarItem.xaml
@@ -6,7 +6,8 @@
 -->
 
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type CalendarItem}"
                 TargetType="CalendarItem">
     <Setter Property="CornerRadius" Value="1" />
diff --git a/src/Avalonia.Themes.Simple/Controls/CaptionButtons.xaml b/src/Avalonia.Themes.Simple/Controls/CaptionButtons.xaml
index 8f68d9809f..e5978919fa 100644
--- a/src/Avalonia.Themes.Simple/Controls/CaptionButtons.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/CaptionButtons.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
diff --git a/src/Avalonia.Themes.Simple/Controls/Carousel.xaml b/src/Avalonia.Themes.Simple/Controls/Carousel.xaml
index 91e331693e..b94ef9b5d9 100644
--- a/src/Avalonia.Themes.Simple/Controls/Carousel.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/Carousel.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type Carousel}" TargetType="Carousel">
     <Setter Property="Template">
       <ControlTemplate>
diff --git a/src/Avalonia.Themes.Simple/Controls/CheckBox.xaml b/src/Avalonia.Themes.Simple/Controls/CheckBox.xaml
index 10e0b883d5..68e969c140 100644
--- a/src/Avalonia.Themes.Simple/Controls/CheckBox.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/CheckBox.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type CheckBox}"
                 TargetType="CheckBox">
     <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/ComboBox.xaml b/src/Avalonia.Themes.Simple/Controls/ComboBox.xaml
index 8b751187d6..a54857abc9 100644
--- a/src/Avalonia.Themes.Simple/Controls/ComboBox.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ComboBox.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ComboBox}"
                 TargetType="ComboBox">
     <Setter Property="Background" Value="Transparent" />
diff --git a/src/Avalonia.Themes.Simple/Controls/ComboBoxItem.xaml b/src/Avalonia.Themes.Simple/Controls/ComboBoxItem.xaml
index c3d8b6f900..da1b964871 100644
--- a/src/Avalonia.Themes.Simple/Controls/ComboBoxItem.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ComboBoxItem.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ComboBoxItem}"
                 TargetType="ComboBoxItem">
     <Setter Property="Background" Value="Transparent" />
diff --git a/src/Avalonia.Themes.Simple/Controls/ContentControl.xaml b/src/Avalonia.Themes.Simple/Controls/ContentControl.xaml
index 415b1dc721..571a276a49 100644
--- a/src/Avalonia.Themes.Simple/Controls/ContentControl.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ContentControl.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ContentControl}"
                 TargetType="ContentControl">
     <Setter Property="Template">
diff --git a/src/Avalonia.Themes.Simple/Controls/ContextMenu.xaml b/src/Avalonia.Themes.Simple/Controls/ContextMenu.xaml
index 3317178979..215f4eec5a 100644
--- a/src/Avalonia.Themes.Simple/Controls/ContextMenu.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ContextMenu.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ContextMenu}"
                 TargetType="ContextMenu">
     <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/DataValidationErrors.xaml b/src/Avalonia.Themes.Simple/Controls/DataValidationErrors.xaml
index a4e5ab2d90..ec5ad87bbc 100644
--- a/src/Avalonia.Themes.Simple/Controls/DataValidationErrors.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/DataValidationErrors.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type DataValidationErrors}"
                 TargetType="DataValidationErrors">
     <Setter Property="Template">
diff --git a/src/Avalonia.Themes.Simple/Controls/DatePicker.xaml b/src/Avalonia.Themes.Simple/Controls/DatePicker.xaml
index 6cf352518a..6ead5019c6 100644
--- a/src/Avalonia.Themes.Simple/Controls/DatePicker.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/DatePicker.xaml
@@ -7,7 +7,8 @@
 
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:sys="using:System">
+                    xmlns:sys="using:System"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Height="500"
             Padding="20">
diff --git a/src/Avalonia.Themes.Simple/Controls/DateTimePickerShared.xaml b/src/Avalonia.Themes.Simple/Controls/DateTimePickerShared.xaml
index 5f1dea692f..5ba4e058ed 100644
--- a/src/Avalonia.Themes.Simple/Controls/DateTimePickerShared.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/DateTimePickerShared.xaml
@@ -6,7 +6,8 @@
 -->
 
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Width="200"
             Padding="20">
diff --git a/src/Avalonia.Themes.Simple/Controls/DropDownButton.xaml b/src/Avalonia.Themes.Simple/Controls/DropDownButton.xaml
index 6a50cd6e36..6d79d420f3 100644
--- a/src/Avalonia.Themes.Simple/Controls/DropDownButton.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/DropDownButton.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type DropDownButton}"
                 TargetType="DropDownButton">
     <Setter Property="Background" Value="{DynamicResource ThemeControlMidBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/EmbeddableControlRoot.xaml b/src/Avalonia.Themes.Simple/Controls/EmbeddableControlRoot.xaml
index 3ea1515cc3..87c940c281 100644
--- a/src/Avalonia.Themes.Simple/Controls/EmbeddableControlRoot.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/EmbeddableControlRoot.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type EmbeddableControlRoot}"
                 TargetType="EmbeddableControlRoot">
     <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/Expander.xaml b/src/Avalonia.Themes.Simple/Controls/Expander.xaml
index 9920c9445a..cdc2894979 100644
--- a/src/Avalonia.Themes.Simple/Controls/Expander.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/Expander.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Width="350"
diff --git a/src/Avalonia.Themes.Simple/Controls/FlyoutPresenter.xaml b/src/Avalonia.Themes.Simple/Controls/FlyoutPresenter.xaml
index 08959cfbbe..b6cf899fd5 100644
--- a/src/Avalonia.Themes.Simple/Controls/FlyoutPresenter.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/FlyoutPresenter.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type FlyoutPresenter}"
                 TargetType="FlyoutPresenter">
     <Setter Property="HorizontalContentAlignment" Value="Stretch" />
diff --git a/src/Avalonia.Themes.Simple/Controls/GridSplitter.xaml b/src/Avalonia.Themes.Simple/Controls/GridSplitter.xaml
index f2a3f01397..c4385ab0b4 100644
--- a/src/Avalonia.Themes.Simple/Controls/GridSplitter.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/GridSplitter.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type GridSplitter}"
                 TargetType="GridSplitter">
     <Setter Property="Focusable" Value="True" />
diff --git a/src/Avalonia.Themes.Simple/Controls/ItemsControl.xaml b/src/Avalonia.Themes.Simple/Controls/ItemsControl.xaml
index 8cf4e0be08..ba6b37fd90 100644
--- a/src/Avalonia.Themes.Simple/Controls/ItemsControl.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ItemsControl.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ItemsControl}"
                 TargetType="ItemsControl">
     <Setter Property="Template">
diff --git a/src/Avalonia.Themes.Simple/Controls/Label.xaml b/src/Avalonia.Themes.Simple/Controls/Label.xaml
index 0faa4852f2..2c9bb15742 100644
--- a/src/Avalonia.Themes.Simple/Controls/Label.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/Label.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type Label}"
                 TargetType="Label">
     <Setter Property="Padding" Value="3" />
diff --git a/src/Avalonia.Themes.Simple/Controls/ListBox.xaml b/src/Avalonia.Themes.Simple/Controls/ListBox.xaml
index a51fcbf72e..eeefa498a7 100644
--- a/src/Avalonia.Themes.Simple/Controls/ListBox.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ListBox.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ListBox}"
                 TargetType="ListBox">
     <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/ListBoxItem.xaml b/src/Avalonia.Themes.Simple/Controls/ListBoxItem.xaml
index 4d918326c8..c2a96c71a6 100644
--- a/src/Avalonia.Themes.Simple/Controls/ListBoxItem.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ListBoxItem.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ListBoxItem}"
                 TargetType="ListBoxItem">
     <Setter Property="Background" Value="Transparent" />
diff --git a/src/Avalonia.Themes.Simple/Controls/ManagedFileChooser.xaml b/src/Avalonia.Themes.Simple/Controls/ManagedFileChooser.xaml
index a5b0649655..24e5247139 100644
--- a/src/Avalonia.Themes.Simple/Controls/ManagedFileChooser.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ManagedFileChooser.xaml
@@ -1,7 +1,8 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:dialogs="using:Avalonia.Dialogs"
-                    xmlns:internal="using:Avalonia.Dialogs.Internal">
+                    xmlns:internal="using:Avalonia.Dialogs.Internal"
+                    x:ClassModifier="internal">
   <DrawingGroup x:Key="LevelUp">
     <GeometryDrawing Brush="#00FFFFFF" Geometry="F1M16,16L0,16 0,0 16,0z" />
     <GeometryDrawing Brush="#FFF6F6F6"
@@ -49,7 +50,7 @@
                 TargetType="dialogs:ManagedFileChooser">
     <Setter Property="Template">
       <ControlTemplate x:DataType="internal:ManagedFileChooserViewModel">
-        <DockPanel>
+        <DockPanel Margin="5">
           <DockPanel Margin="0,0,0,5"
                      DockPanel.Dock="Top">
             <internal:ChildFitter Width="{Binding ElementName=Location, Path=Bounds.Height}"
@@ -93,8 +94,8 @@
                   <Setter Property="Margin" Value="4" />
                 </Style>
               </StackPanel.Styles>
-              <Button Command="{Binding Ok}">OK</Button>
-              <Button Command="{Binding Cancel}">Cancel</Button>
+              <Button Command="{Binding Ok}" MinWidth="60">OK</Button>
+              <Button Command="{Binding Cancel}" MinWidth="60">Cancel</Button>
             </StackPanel>
           </DockPanel>
 
@@ -136,7 +137,6 @@
                   DockPanel.Dock="Top">
               <Grid.ColumnDefinitions>
                 <ColumnDefinition Width="20" SharedSizeGroup="Icon" />
-                <ColumnDefinition Width="16" SharedSizeGroup="Splitter" />
                 <ColumnDefinition Width="400" SharedSizeGroup="Name" />
                 <ColumnDefinition Width="16" SharedSizeGroup="Splitter" />
                 <ColumnDefinition Width="200" SharedSizeGroup="Modified" />
@@ -144,19 +144,45 @@
                 <ColumnDefinition Width="150" SharedSizeGroup="Type" />
                 <ColumnDefinition Width="16" SharedSizeGroup="Splitter" />
                 <ColumnDefinition Width="200" SharedSizeGroup="Size" />
+                <ColumnDefinition Width="16" SharedSizeGroup="Splitter" />
               </Grid.ColumnDefinitions>
-              <GridSplitter Grid.Column="1" />
-              <TextBlock Grid.Column="2"
+              <TextBlock Grid.Column="1"
                          Text="Name" />
-              <GridSplitter Grid.Column="3" />
-              <TextBlock Grid.Column="4"
+              <GridSplitter Grid.Column="2"
+                            ResizeDirection="Columns"
+                            Background="Transparent" />
+              <Rectangle HorizontalAlignment="Left" Grid.Column="2" VerticalAlignment="Stretch" Width="1" Fill="{DynamicResource ThemeControlMidBrush}"/>
+              <TextBlock Grid.Column="3"
                          Text="Date Modified" />
-              <GridSplitter Grid.Column="5" />
-              <TextBlock Grid.Column="6"
+              <GridSplitter Grid.Column="4"
+                            ResizeDirection="Columns"
+                            Background="Transparent" />
+              <Rectangle HorizontalAlignment="Left"
+                         Grid.Column="4"
+                         VerticalAlignment="Stretch"
+                         Width="1"
+                         Fill="{DynamicResource ThemeControlMidBrush}"/>
+
+              <TextBlock Grid.Column="5"
                          Text="Type" />
-              <GridSplitter Grid.Column="7" />
-              <TextBlock Grid.Column="8"
+              <GridSplitter Grid.Column="6" ResizeDirection="Columns"
+                            Background="Transparent" />
+              <Rectangle HorizontalAlignment="Left"
+                         Grid.Column="6"
+                         VerticalAlignment="Stretch"
+                         Width="1"
+                         Fill="{DynamicResource ThemeControlMidBrush}"/>
+
+              <TextBlock Grid.Column="7"
                          Text="Size" />
+              <GridSplitter Grid.Column="8"
+                            ResizeDirection="Columns"
+                            Background="Transparent" />
+              <Rectangle HorizontalAlignment="Left"
+                         Grid.Column="8"
+                         VerticalAlignment="Stretch"
+                         Width="1"
+                         Fill="{DynamicResource ThemeControlMidBrush}"/>
             </Grid>
             <ListBox x:Name="PART_Files"
                      Margin="0,5"
@@ -169,7 +195,6 @@
                   <Grid Background="Transparent">
                     <Grid.ColumnDefinitions>
                       <ColumnDefinition SharedSizeGroup="Icon" />
-                      <ColumnDefinition SharedSizeGroup="Splitter" />
                       <ColumnDefinition SharedSizeGroup="Name" />
                       <ColumnDefinition SharedSizeGroup="Splitter" />
                       <ColumnDefinition SharedSizeGroup="Modified" />
@@ -177,19 +202,20 @@
                       <ColumnDefinition SharedSizeGroup="Type" />
                       <ColumnDefinition SharedSizeGroup="Splitter" />
                       <ColumnDefinition SharedSizeGroup="Size" />
+                      <ColumnDefinition SharedSizeGroup="Splitter" />
                     </Grid.ColumnDefinitions>
                     <Image Grid.Column="0"
                            Width="16"
                            Height="16">
                       <DrawingImage Drawing="{Binding IconKey, Converter={StaticResource Icons}}" />
                     </Image>
-                    <TextBlock Grid.Column="2"
+                    <TextBlock Grid.Column="1"
                                Text="{Binding DisplayName}" />
-                    <TextBlock Grid.Column="4"
+                    <TextBlock Grid.Column="3"
                                Text="{Binding Modified}" />
-                    <TextBlock Grid.Column="6"
+                    <TextBlock Grid.Column="5"
                                Text="{Binding Type}" />
-                    <TextBlock Grid.Column="8">
+                    <TextBlock Grid.Column="7" HorizontalAlignment="Right">
                       <TextBlock.Text>
                         <Binding Path="Size">
                           <Binding.Converter>
diff --git a/src/Avalonia.Themes.Simple/Controls/Menu.xaml b/src/Avalonia.Themes.Simple/Controls/Menu.xaml
index c64527d63c..1024cae7a4 100644
--- a/src/Avalonia.Themes.Simple/Controls/Menu.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/Menu.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:sys="using:System">
+                    xmlns:sys="using:System"
+                    x:ClassModifier="internal">
 
   <ControlTheme x:Key="SimpleTopLevelMenuItem"
                 TargetType="MenuItem">
diff --git a/src/Avalonia.Themes.Simple/Controls/MenuFlyoutPresenter.xaml b/src/Avalonia.Themes.Simple/Controls/MenuFlyoutPresenter.xaml
index 05337d774f..73835b8155 100644
--- a/src/Avalonia.Themes.Simple/Controls/MenuFlyoutPresenter.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/MenuFlyoutPresenter.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type MenuFlyoutPresenter}"
                 TargetType="MenuFlyoutPresenter">
     <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/MenuItem.xaml b/src/Avalonia.Themes.Simple/Controls/MenuItem.xaml
index 59ddcdf325..063c0d3d68 100644
--- a/src/Avalonia.Themes.Simple/Controls/MenuItem.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/MenuItem.xaml
@@ -1,7 +1,8 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:conv="using:Avalonia.Controls.Converters"
-                    xmlns:sys="using:System">
+                    xmlns:sys="using:System"
+                    x:ClassModifier="internal">
   <conv:PlatformKeyGestureConverter x:Key="KeyGestureConverter" />
 
   <ControlTheme x:Key="{x:Type MenuItem}"
diff --git a/src/Avalonia.Themes.Simple/Controls/NativeMenuBar.xaml b/src/Avalonia.Themes.Simple/Controls/NativeMenuBar.xaml
index 625bf71e66..9139f96a2a 100644
--- a/src/Avalonia.Themes.Simple/Controls/NativeMenuBar.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/NativeMenuBar.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:default="using:Avalonia.Themes.Simple">
+                    xmlns:default="using:Avalonia.Themes.Simple"
+                    x:ClassModifier="internal">
   <default:IBitmapToImageConverter x:Key="AvaloniaThemesSimpleNativeMenuBarIBitmapToImageConverter" />
   <ControlTheme x:Key="{x:Type NativeMenuBar}"
                 TargetType="NativeMenuBar">
diff --git a/src/Avalonia.Themes.Simple/Controls/NotificationCard.xaml b/src/Avalonia.Themes.Simple/Controls/NotificationCard.xaml
index 524f964afc..62e73a8dd0 100644
--- a/src/Avalonia.Themes.Simple/Controls/NotificationCard.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/NotificationCard.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type NotificationCard}"
                 TargetType="NotificationCard">
     <Setter Property="Background" Value="{DynamicResource NotificationCardBackgroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/NumericUpDown.xaml b/src/Avalonia.Themes.Simple/Controls/NumericUpDown.xaml
index d3adfb31e0..4ce6a20dc6 100644
--- a/src/Avalonia.Themes.Simple/Controls/NumericUpDown.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/NumericUpDown.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type NumericUpDown}"
                 TargetType="NumericUpDown">
     <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/OverlayPopupHost.xaml b/src/Avalonia.Themes.Simple/Controls/OverlayPopupHost.xaml
index 4c7864473b..c70721aac7 100644
--- a/src/Avalonia.Themes.Simple/Controls/OverlayPopupHost.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/OverlayPopupHost.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type OverlayPopupHost}"
                 TargetType="OverlayPopupHost">
     <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/PathIcon.xaml b/src/Avalonia.Themes.Simple/Controls/PathIcon.xaml
index 4116b5784e..9e39ba4645 100644
--- a/src/Avalonia.Themes.Simple/Controls/PathIcon.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/PathIcon.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type PathIcon}"
                 TargetType="PathIcon">
     <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundColor}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/PopupRoot.xaml b/src/Avalonia.Themes.Simple/Controls/PopupRoot.xaml
index 33c8d0764e..aaf51a2cef 100644
--- a/src/Avalonia.Themes.Simple/Controls/PopupRoot.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/PopupRoot.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type PopupRoot}"
                 TargetType="PopupRoot">
     <Setter Property="Background" Value="{x:Null}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/ProgressBar.xaml b/src/Avalonia.Themes.Simple/Controls/ProgressBar.xaml
index 1f4bf006a0..e7ad33d04e 100644
--- a/src/Avalonia.Themes.Simple/Controls/ProgressBar.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ProgressBar.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:converters="using:Avalonia.Controls.Converters">
+                    xmlns:converters="using:Avalonia.Controls.Converters"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="10">
@@ -86,10 +87,10 @@
                    IterationCount="Infinite"
                    Duration="0:0:3">
           <KeyFrame Cue="0%">
-            <Setter Property="TranslateTransform.X" Value="{Binding IndeterminateStartingOffset, RelativeSource={RelativeSource TemplatedParent}}" />
+            <Setter Property="TranslateTransform.X" Value="{Binding $parent[ProgressBar].TemplateSettings.IndeterminateStartingOffset}" />
           </KeyFrame>
           <KeyFrame Cue="100%">
-            <Setter Property="TranslateTransform.X" Value="{Binding IndeterminateEndingOffset, RelativeSource={RelativeSource TemplatedParent}}" />
+            <Setter Property="TranslateTransform.X" Value="{Binding $parent[ProgressBar].TemplateSettings.IndeterminateEndingOffset}" />
           </KeyFrame>
         </Animation>
       </Style.Animations>
@@ -101,10 +102,10 @@
                    IterationCount="Infinite"
                    Duration="0:0:3">
           <KeyFrame Cue="0%">
-            <Setter Property="TranslateTransform.Y" Value="{Binding IndeterminateStartingOffset, RelativeSource={RelativeSource TemplatedParent}}" />
+            <Setter Property="TranslateTransform.Y" Value="{Binding $parent[ProgressBar].TemplateSettings.IndeterminateStartingOffset}" />
           </KeyFrame>
           <KeyFrame Cue="100%">
-            <Setter Property="TranslateTransform.Y" Value="{Binding IndeterminateEndingOffset, RelativeSource={RelativeSource TemplatedParent}}" />
+            <Setter Property="TranslateTransform.Y" Value="{Binding $parent[ProgressBar].TemplateSettings.IndeterminateEndingOffset}" />
           </KeyFrame>
         </Animation>
       </Style.Animations>
diff --git a/src/Avalonia.Themes.Simple/Controls/RadioButton.xaml b/src/Avalonia.Themes.Simple/Controls/RadioButton.xaml
index c837b44402..ea138d8806 100644
--- a/src/Avalonia.Themes.Simple/Controls/RadioButton.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/RadioButton.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type RadioButton}"
                 TargetType="RadioButton">
     <Setter Property="Background" Value="Transparent" />
diff --git a/src/Avalonia.Themes.Simple/Controls/RefreshContainer.xaml b/src/Avalonia.Themes.Simple/Controls/RefreshContainer.xaml
index 04b2a1bf29..0a293cc977 100644
--- a/src/Avalonia.Themes.Simple/Controls/RefreshContainer.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/RefreshContainer.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type RefreshContainer}"
                 TargetType="RefreshContainer">
     <Setter Property="Template">
diff --git a/src/Avalonia.Themes.Simple/Controls/RefreshVisualizer.xaml b/src/Avalonia.Themes.Simple/Controls/RefreshVisualizer.xaml
index bd7e43530a..09f15e4b2a 100644
--- a/src/Avalonia.Themes.Simple/Controls/RefreshVisualizer.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/RefreshVisualizer.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type RefreshVisualizer}"
                 TargetType="RefreshVisualizer">
     <Setter Property="IsTabStop"
diff --git a/src/Avalonia.Themes.Simple/Controls/RepeatButton.xaml b/src/Avalonia.Themes.Simple/Controls/RepeatButton.xaml
index 73cfd4d810..9da320a79d 100644
--- a/src/Avalonia.Themes.Simple/Controls/RepeatButton.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/RepeatButton.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type RepeatButton}"
                 TargetType="RepeatButton">
     <Setter Property="Background" Value="{DynamicResource ThemeControlMidBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/ScrollBar.xaml b/src/Avalonia.Themes.Simple/Controls/ScrollBar.xaml
index d28ba66f6d..8b647c8299 100644
--- a/src/Avalonia.Themes.Simple/Controls/ScrollBar.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ScrollBar.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ScrollBar}"
                 TargetType="ScrollBar">
     <Setter Property="Cursor" Value="Arrow" />
diff --git a/src/Avalonia.Themes.Simple/Controls/ScrollViewer.xaml b/src/Avalonia.Themes.Simple/Controls/ScrollViewer.xaml
index 4f6fc5f322..2b36b118c3 100644
--- a/src/Avalonia.Themes.Simple/Controls/ScrollViewer.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ScrollViewer.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:converters="using:Avalonia.Controls.Converters">
+                    xmlns:converters="using:Avalonia.Controls.Converters"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ScrollViewer}"
                 TargetType="ScrollViewer">
     <Setter Property="Background" Value="Transparent" />
diff --git a/src/Avalonia.Themes.Simple/Controls/SelectableTextBlock.xaml b/src/Avalonia.Themes.Simple/Controls/SelectableTextBlock.xaml
index e504a8cf8e..504e727fa0 100644
--- a/src/Avalonia.Themes.Simple/Controls/SelectableTextBlock.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/SelectableTextBlock.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <SelectableTextBlock Text="Preview" />
   </Design.PreviewWith>
diff --git a/src/Avalonia.Themes.Simple/Controls/Separator.xaml b/src/Avalonia.Themes.Simple/Controls/Separator.xaml
index e142cf29ad..0d7202c8b4 100644
--- a/src/Avalonia.Themes.Simple/Controls/Separator.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/Separator.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type Separator}"
                 TargetType="Separator">
     <Setter Property="Focusable" Value="False" />
diff --git a/src/Avalonia.Themes.Simple/Controls/SimpleControls.xaml b/src/Avalonia.Themes.Simple/Controls/SimpleControls.xaml
index dc533488c9..3b4a1d8104 100644
--- a/src/Avalonia.Themes.Simple/Controls/SimpleControls.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/SimpleControls.xaml
@@ -1,5 +1,6 @@
 <Styles xmlns="https://github.com/avaloniaui"
-        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:ClassModifier="internal">
   <Styles.Resources>
     <ResourceDictionary>
       <ResourceDictionary.MergedDictionaries>
diff --git a/src/Avalonia.Themes.Simple/Controls/Slider.xaml b/src/Avalonia.Themes.Simple/Controls/Slider.xaml
index 851ee1b78a..da840dbbd5 100644
--- a/src/Avalonia.Themes.Simple/Controls/Slider.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/Slider.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="SliderRepeatTrackTheme"
                 TargetType="RepeatButton">
     <Setter Property="Background" Value="Transparent" />
diff --git a/src/Avalonia.Themes.Simple/Controls/SplitButton.xaml b/src/Avalonia.Themes.Simple/Controls/SplitButton.xaml
index 2a7dc081f0..7562c9151e 100644
--- a/src/Avalonia.Themes.Simple/Controls/SplitButton.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/SplitButton.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:converters="using:Avalonia.Controls.Converters">
+                    xmlns:converters="using:Avalonia.Controls.Converters"
+                    x:ClassModifier="internal">
 
   <!-- This style is based on the Fluent v1 style. -->
 
diff --git a/src/Avalonia.Themes.Simple/Controls/SplitView.xaml b/src/Avalonia.Themes.Simple/Controls/SplitView.xaml
index f839e9a598..8d4851add8 100644
--- a/src/Avalonia.Themes.Simple/Controls/SplitView.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/SplitView.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:sys="using:System">
+                    xmlns:sys="using:System"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Width="400" Height="400">
       <SplitView DisplayMode="Inline"
diff --git a/src/Avalonia.Themes.Simple/Controls/TabControl.xaml b/src/Avalonia.Themes.Simple/Controls/TabControl.xaml
index c3cecb4fb8..beb6782098 100644
--- a/src/Avalonia.Themes.Simple/Controls/TabControl.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TabControl.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type TabControl}"
                 TargetType="TabControl">
     <Setter Property="Padding" Value="8" />
diff --git a/src/Avalonia.Themes.Simple/Controls/TabItem.xaml b/src/Avalonia.Themes.Simple/Controls/TabItem.xaml
index 7b6a1d1116..50a269bf79 100644
--- a/src/Avalonia.Themes.Simple/Controls/TabItem.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TabItem.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type TabItem}"
                 TargetType="TabItem">
     <Setter Property="Background" Value="Transparent" />
diff --git a/src/Avalonia.Themes.Simple/Controls/TabStrip.xaml b/src/Avalonia.Themes.Simple/Controls/TabStrip.xaml
index fd12eaa258..9d08c73453 100644
--- a/src/Avalonia.Themes.Simple/Controls/TabStrip.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TabStrip.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type TabStrip}"
                 TargetType="TabStrip">
     <Setter Property="Template">
diff --git a/src/Avalonia.Themes.Simple/Controls/TabStripItem.xaml b/src/Avalonia.Themes.Simple/Controls/TabStripItem.xaml
index b4d7218ec3..f0609bf66b 100644
--- a/src/Avalonia.Themes.Simple/Controls/TabStripItem.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TabStripItem.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type TabStripItem}"
                 TargetType="TabStripItem">
     <Setter Property="Background" Value="Transparent" />
diff --git a/src/Avalonia.Themes.Simple/Controls/TextBox.xaml b/src/Avalonia.Themes.Simple/Controls/TextBox.xaml
index b42d52a920..63da3cee44 100644
--- a/src/Avalonia.Themes.Simple/Controls/TextBox.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TextBox.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <StreamGeometry x:Key="TextBoxClearButtonData">M 11.416016,10 20,1.4160156 18.583984,0 10,8.5839846 1.4160156,0 0,1.4160156 8.5839844,10 0,18.583985 1.4160156,20 10,11.416015 18.583984,20 20,18.583985 Z</StreamGeometry>
   <StreamGeometry x:Key="PasswordBoxRevealButtonData">m10.051 7.0032c2.215 0 4.0105 1.7901 4.0105 3.9984s-1.7956 3.9984-4.0105 3.9984c-2.215 0-4.0105-1.7901-4.0105-3.9984s1.7956-3.9984 4.0105-3.9984zm0 1.4994c-1.3844 0-2.5066 1.1188-2.5066 2.499s1.1222 2.499 2.5066 2.499 2.5066-1.1188 2.5066-2.499-1.1222-2.499-2.5066-2.499zm0-5.0026c4.6257 0 8.6188 3.1487 9.7267 7.5613 0.10085 0.40165-0.14399 0.80877-0.54686 0.90931-0.40288 0.10054-0.81122-0.14355-0.91208-0.54521-0.94136-3.7492-4.3361-6.4261-8.2678-6.4261-3.9334 0-7.3292 2.6792-8.2689 6.4306-0.10063 0.40171-0.50884 0.64603-0.91177 0.54571s-0.648-0.5073-0.54737-0.90901c1.106-4.4152 5.1003-7.5667 9.728-7.5667z</StreamGeometry>
   <StreamGeometry x:Key="PasswordBoxHideButtonData">m0.21967 0.21965c-0.26627 0.26627-0.29047 0.68293-0.07262 0.97654l0.07262 0.08412 4.0346 4.0346c-1.922 1.3495-3.3585 3.365-3.9554 5.7495-0.10058 0.4018 0.14362 0.8091 0.54543 0.9097 0.40182 0.1005 0.80909-0.1436 0.90968-0.5455 0.52947-2.1151 1.8371-3.8891 3.5802-5.0341l1.8096 1.8098c-0.70751 0.7215-1.1438 1.71-1.1438 2.8003 0 2.2092 1.7909 4 4 4 1.0904 0 2.0788-0.4363 2.8004-1.1438l5.9193 5.9195c0.2929 0.2929 0.7677 0.2929 1.0606 0 0.2663-0.2662 0.2905-0.6829 0.0726-0.9765l-0.0726-0.0841-6.1135-6.1142 0.0012-0.0015-1.2001-1.1979-2.8699-2.8693 2e-3 -8e-4 -2.8812-2.8782 0.0012-0.0018-1.1333-1.1305-4.3064-4.3058c-0.29289-0.29289-0.76777-0.29289-1.0607 0zm7.9844 9.0458 3.5351 3.5351c-0.45 0.4358-1.0633 0.704-1.7392 0.704-1.3807 0-2.5-1.1193-2.5-2.5 0-0.6759 0.26824-1.2892 0.7041-1.7391zm1.7959-5.7655c-1.0003 0-1.9709 0.14807-2.8889 0.425l1.237 1.2362c0.5358-0.10587 1.0883-0.16119 1.6519-0.16119 3.9231 0 7.3099 2.6803 8.2471 6.4332 0.1004 0.4018 0.5075 0.6462 0.9094 0.5459 0.4019-0.1004 0.6463-0.5075 0.5459-0.9094-1.103-4.417-5.0869-7.5697-9.7024-7.5697zm0.1947 3.5093 3.8013 3.8007c-0.1018-2.0569-1.7488-3.7024-3.8013-3.8007z</StreamGeometry>
@@ -123,7 +124,8 @@
                 <ContentPresenter Grid.Column="0"
                                   Grid.ColumnSpan="1"
                                   Content="{TemplateBinding InnerLeftContent}" />
-                <ScrollViewer Grid.Column="1"
+                <ScrollViewer Name="PART_ScrollViewer"
+                              Grid.Column="1"
                               Grid.ColumnSpan="1"
                               AllowAutoHide="{TemplateBinding (ScrollViewer.AllowAutoHide)}"
                               BringIntoViewOnFocusChange="{TemplateBinding (ScrollViewer.BringIntoViewOnFocusChange)}"
diff --git a/src/Avalonia.Themes.Simple/Controls/ThemeVariantScope.xaml b/src/Avalonia.Themes.Simple/Controls/ThemeVariantScope.xaml
index a6022fb263..2eb157cf6b 100644
--- a/src/Avalonia.Themes.Simple/Controls/ThemeVariantScope.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ThemeVariantScope.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ThemeVariantScope}"
                 TargetType="ThemeVariantScope">
     <Setter Property="TextElement.Foreground" Value="{DynamicResource ThemeForegroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/TimePicker.xaml b/src/Avalonia.Themes.Simple/Controls/TimePicker.xaml
index 5acbc41a68..adac54a262 100644
--- a/src/Avalonia.Themes.Simple/Controls/TimePicker.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TimePicker.xaml
@@ -7,7 +7,8 @@
 
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:sys="using:System">
+                    xmlns:sys="using:System"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border Height="500"
             Padding="20">
diff --git a/src/Avalonia.Themes.Simple/Controls/TitleBar.xaml b/src/Avalonia.Themes.Simple/Controls/TitleBar.xaml
index a06dfbb834..67b1eae9da 100644
--- a/src/Avalonia.Themes.Simple/Controls/TitleBar.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TitleBar.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <Border>
       <TitleBar Width="300"
diff --git a/src/Avalonia.Themes.Simple/Controls/ToggleButton.xaml b/src/Avalonia.Themes.Simple/Controls/ToggleButton.xaml
index 2cfbcf6b7a..ad05f15f84 100644
--- a/src/Avalonia.Themes.Simple/Controls/ToggleButton.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ToggleButton.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ToggleButton}"
                 TargetType="ToggleButton">
     <Setter Property="Background" Value="{DynamicResource ThemeControlMidBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/ToggleSwitch.xaml b/src/Avalonia.Themes.Simple/Controls/ToggleSwitch.xaml
index f7223c46c0..a51aeb9ee6 100644
--- a/src/Avalonia.Themes.Simple/Controls/ToggleSwitch.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ToggleSwitch.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <Design.PreviewWith>
     <StackPanel Margin="20" Width="250" Spacing="24">
       <StackPanel Spacing="12">
diff --git a/src/Avalonia.Themes.Simple/Controls/ToolTip.xaml b/src/Avalonia.Themes.Simple/Controls/ToolTip.xaml
index c4fddd8c4c..2c67e2c650 100644
--- a/src/Avalonia.Themes.Simple/Controls/ToolTip.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/ToolTip.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type ToolTip}"
                 TargetType="ToolTip">
     <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/TransitioningContentControl.xaml b/src/Avalonia.Themes.Simple/Controls/TransitioningContentControl.xaml
index fa8d749b1f..ceccdf56c7 100644
--- a/src/Avalonia.Themes.Simple/Controls/TransitioningContentControl.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TransitioningContentControl.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type TransitioningContentControl}"
                 TargetType="TransitioningContentControl">
     <!--  Set Defaults  -->
diff --git a/src/Avalonia.Themes.Simple/Controls/TreeView.xaml b/src/Avalonia.Themes.Simple/Controls/TreeView.xaml
index f2f451fe6f..d76bf6c393 100644
--- a/src/Avalonia.Themes.Simple/Controls/TreeView.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TreeView.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type TreeView}"
                 TargetType="TreeView">
     <Setter Property="Background" Value="Transparent" />
diff --git a/src/Avalonia.Themes.Simple/Controls/TreeViewItem.xaml b/src/Avalonia.Themes.Simple/Controls/TreeViewItem.xaml
index 8e85bcbd44..c3c3801ec0 100644
--- a/src/Avalonia.Themes.Simple/Controls/TreeViewItem.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/TreeViewItem.xaml
@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:converters="using:Avalonia.Controls.Converters">
+                    xmlns:converters="using:Avalonia.Controls.Converters"
+                    x:ClassModifier="internal">
   <converters:MarginMultiplierConverter x:Key="LeftMarginConverter"
                                         Indent="16"
                                         Left="True" />
diff --git a/src/Avalonia.Themes.Simple/Controls/UserControl.xaml b/src/Avalonia.Themes.Simple/Controls/UserControl.xaml
index 3316b0298c..7f33b803d7 100644
--- a/src/Avalonia.Themes.Simple/Controls/UserControl.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/UserControl.xaml
@@ -1,6 +1,7 @@
 <Style xmlns="https://github.com/avaloniaui"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-       Selector=":is(UserControl)">
+       Selector=":is(UserControl)"
+       x:ClassModifier="internal">
   <Style.Resources>
     <ControlTheme x:Key="SimpleUserControl"
                   TargetType="UserControl">
diff --git a/src/Avalonia.Themes.Simple/Controls/Window.xaml b/src/Avalonia.Themes.Simple/Controls/Window.xaml
index 0a0363c2d0..1a1c9f40cd 100644
--- a/src/Avalonia.Themes.Simple/Controls/Window.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/Window.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type Window}"
                 TargetType="Window">
     <Setter Property="FontFamily" Value="{DynamicResource ContentControlThemeFontFamily}" />
diff --git a/src/Avalonia.Themes.Simple/Controls/WindowNotificationManager.xaml b/src/Avalonia.Themes.Simple/Controls/WindowNotificationManager.xaml
index 6dacf63be5..ede24fd6eb 100644
--- a/src/Avalonia.Themes.Simple/Controls/WindowNotificationManager.xaml
+++ b/src/Avalonia.Themes.Simple/Controls/WindowNotificationManager.xaml
@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    x:ClassModifier="internal">
   <ControlTheme x:Key="{x:Type WindowNotificationManager}"
                 TargetType="WindowNotificationManager">
     <Setter Property="Margin" Value="0 0 8 8" />
diff --git a/src/Avalonia.X11/TransparencyHelper.cs b/src/Avalonia.X11/TransparencyHelper.cs
index 5ca2d1d337..3cc901e332 100644
--- a/src/Avalonia.X11/TransparencyHelper.cs
+++ b/src/Avalonia.X11/TransparencyHelper.cs
@@ -1,6 +1,9 @@
 using System;
+using System.Collections.Generic;
 using Avalonia.Controls;
 
+#nullable enable
+
 namespace Avalonia.X11
 {
     internal class TransparencyHelper :  IDisposable, X11Globals.IGlobalsSubscriber
@@ -9,11 +12,23 @@ namespace Avalonia.X11
         private readonly IntPtr _window;
         private readonly X11Globals _globals;
         private WindowTransparencyLevel _currentLevel;
-        private WindowTransparencyLevel _requestedLevel;
+        private IReadOnlyList<WindowTransparencyLevel>? _requestedLevels;
         private bool _blurAtomsAreSet;
         
-        public Action<WindowTransparencyLevel> TransparencyLevelChanged { get; set; }
-        public WindowTransparencyLevel CurrentLevel => _currentLevel;
+        public Action<WindowTransparencyLevel>? TransparencyLevelChanged { get; set; }
+        
+        public WindowTransparencyLevel CurrentLevel
+        {
+            get => _currentLevel;
+            set
+            {
+                if (_currentLevel != value)
+                {
+                    _currentLevel = value;
+                    TransparencyLevelChanged?.Invoke(value);
+                }
+            }
+        }
 
         public TransparencyHelper(X11Info x11, IntPtr window, X11Globals globals)
         {
@@ -23,25 +38,53 @@ namespace Avalonia.X11
             _globals.AddSubscriber(this);
         }
 
-        public void SetTransparencyRequest(WindowTransparencyLevel level)
+        public void SetTransparencyRequest(IReadOnlyList<WindowTransparencyLevel> levels)
+        {
+            _requestedLevels = levels;
+
+            foreach (var level in levels)
+            {
+                if (!IsSupported(level))
+                    continue;
+
+                SetBlur(level == WindowTransparencyLevel.Blur);
+                CurrentLevel = level;
+                return;
+            }
+
+            // If we get here, we didn't find a supported level. Use the defualt of Transparent or
+            // None, depending on whether composition is enabled.
+            SetBlur(false);
+            CurrentLevel = _globals.IsCompositionEnabled ?
+                WindowTransparencyLevel.Transparent :
+                WindowTransparencyLevel.None;
+        }
+
+        private bool IsSupported(WindowTransparencyLevel level)
         {
-            _requestedLevel = level;
-            UpdateTransparency();
+            // None is suppported when composition is disabled.
+            if (level == WindowTransparencyLevel.None)
+                return !_globals.IsCompositionEnabled;
+
+            // Transparent is suppported when composition is enabled.
+            if (level == WindowTransparencyLevel.Transparent)
+                return _globals.IsCompositionEnabled;
+
+            // Blur is supported when composition is enabled and KWin is used.
+            if (level == WindowTransparencyLevel.Blur)
+                return _globals.IsCompositionEnabled && _globals.WmName == "KWin";
+            
+            return false;
         }
 
         private void UpdateTransparency()
         {
-            var newLevel = UpdateAtomsAndGetTransparency();
-            if (newLevel != _currentLevel)
-            {
-                _currentLevel = newLevel;
-                TransparencyLevelChanged?.Invoke(newLevel);
-            }
+            SetTransparencyRequest(_requestedLevels ?? Array.Empty<WindowTransparencyLevel>());
         }
-        
-        private WindowTransparencyLevel UpdateAtomsAndGetTransparency()
+
+        private void SetBlur(bool blur)
         {
-            if (_requestedLevel >= WindowTransparencyLevel.Blur)
+            if (blur)
             {
                 if (!_blurAtomsAreSet)
                 {
@@ -59,15 +102,7 @@ namespace Avalonia.X11
                     _blurAtomsAreSet = false;
                 }
             }
-
-            if (!_globals.IsCompositionEnabled)
-                return WindowTransparencyLevel.None;
-            if (_requestedLevel >= WindowTransparencyLevel.Blur && CanBlur)
-                return WindowTransparencyLevel.Blur;
-            return WindowTransparencyLevel.Transparent;
         }
-
-        private bool CanBlur => _globals.WmName == "KWin" && _globals.IsCompositionEnabled;
         
         public void Dispose()
         {
diff --git a/src/Avalonia.X11/X11Platform.cs b/src/Avalonia.X11/X11Platform.cs
index fc8b6f2ed6..a880e4ba1a 100644
--- a/src/Avalonia.X11/X11Platform.cs
+++ b/src/Avalonia.X11/X11Platform.cs
@@ -75,7 +75,6 @@ namespace Avalonia.X11
                 .Bind<IWindowingPlatform>().ToConstant(this)
                 .Bind<IDispatcherImpl>().ToConstant(new X11PlatformThreading(this))
                 .Bind<IRenderTimer>().ToConstant(new SleepLoopRenderTimer(60))
-                .Bind<IRenderLoop>().ToConstant(new RenderLoop())
                 .Bind<PlatformHotkeyConfiguration>().ToConstant(new PlatformHotkeyConfiguration(KeyModifiers.Control))
                 .Bind<IKeyboardDevice>().ToFunc(() => KeyboardDevice)
                 .Bind<ICursorFactory>().ToConstant(new X11CursorFactory(Display))
@@ -104,7 +103,7 @@ namespace Avalonia.X11
 
             var gl = AvaloniaLocator.Current.GetService<IPlatformGraphics>();
 
-            Compositor = new Compositor(AvaloniaLocator.Current.GetRequiredService<IRenderLoop>(), gl);
+            Compositor = new Compositor(gl);
         }
 
         public IntPtr DeferredDisplay { get; set; }
diff --git a/src/Avalonia.X11/X11Window.cs b/src/Avalonia.X11/X11Window.cs
index 0a535d2f57..be2d754819 100644
--- a/src/Avalonia.X11/X11Window.cs
+++ b/src/Avalonia.X11/X11Window.cs
@@ -196,7 +196,7 @@ namespace Avalonia.X11
             _rawEventGrouper = new RawEventGrouper(DispatchInput, platform.EventGrouperDispatchQueue);
             
             _transparencyHelper = new TransparencyHelper(_x11, _handle, platform.Globals);
-            _transparencyHelper.SetTransparencyRequest(WindowTransparencyLevel.None);
+            _transparencyHelper.SetTransparencyRequest(Array.Empty<WindowTransparencyLevel>());
 
             CreateIC();
 
@@ -382,9 +382,8 @@ namespace Avalonia.X11
         public Action<PixelPoint>? PositionChanged { get; set; }
         public Action? LostFocus { get; set; }
 
-        public IRenderer CreateRenderer(IRenderRoot root) =>
-            new CompositingRenderer(root, _platform.Compositor, () => Surfaces);
-
+        public Compositor Compositor => _platform.Compositor;
+        
         private void OnEvent(ref XEvent ev)
         {
             if (_inputRoot is null)
@@ -511,7 +510,7 @@ namespace Avalonia.X11
                         if (changedSize && !updatedSizeViaScaling && !_popup)
                             Resized?.Invoke(ClientSize, WindowResizeReason.Unspecified);
 
-                    }, DispatcherPriority.Layout);
+                    }, DispatcherPriority.AsyncRenderTargetResize);
                 if (_useRenderWindow)
                     XConfigureResizeWindow(_x11.Display, _renderHandle, ev.ConfigureEvent.width,
                         ev.ConfigureEvent.height);
@@ -796,7 +795,7 @@ namespace Avalonia.X11
                 {
                     _triggeredExpose = false;
                     DoPaint();
-                }, DispatcherPriority.Render);
+                }, DispatcherPriority.UiThreadRender);
             }
         }
 
@@ -1307,8 +1306,10 @@ namespace Avalonia.X11
 
         public IPopupPositioner? PopupPositioner { get; }
 
-        public void SetTransparencyLevelHint(WindowTransparencyLevel transparencyLevel) =>
-            _transparencyHelper?.SetTransparencyRequest(transparencyLevel);
+        public void SetTransparencyLevelHint(IReadOnlyList<WindowTransparencyLevel> transparencyLevels)
+        {
+            _transparencyHelper?.SetTransparencyRequest(transparencyLevels);
+        }
 
         public void SetWindowManagerAddShadowHint(bool enabled)
         {
@@ -1325,7 +1326,7 @@ namespace Avalonia.X11
 
         public bool IsEnabled => !_disabled;
 
-        public class SurfacePlatformHandle : IPlatformNativeSurfaceHandle
+        public class SurfacePlatformHandle : INativePlatformHandleSurface
         {
             private readonly X11Window _owner;
 
diff --git a/src/Browser/Avalonia.Browser/AvaloniaView.cs b/src/Browser/Avalonia.Browser/AvaloniaView.cs
index 8e1f643b3e..b5dd08d854 100644
--- a/src/Browser/Avalonia.Browser/AvaloniaView.cs
+++ b/src/Browser/Avalonia.Browser/AvaloniaView.cs
@@ -12,6 +12,7 @@ using Avalonia.Controls.Platform;
 using Avalonia.Input;
 using Avalonia.Input.Raw;
 using Avalonia.Input.TextInput;
+using Avalonia.Media;
 using Avalonia.Platform;
 using Avalonia.Rendering.Composition;
 using Avalonia.Threading;
@@ -472,7 +473,7 @@ namespace Avalonia.Browser
 
             if (_topLevel.Renderer is CompositingRenderer dr)
             {
-                dr.CompositionTarget.ImmediateUIThreadRender();
+                MediaContext.Instance.ImmediateRenderRequested(dr.CompositionTarget);
             }
         }
 
diff --git a/src/Browser/Avalonia.Browser/BrowserTopLevelImpl.cs b/src/Browser/Avalonia.Browser/BrowserTopLevelImpl.cs
index 8456dc92d0..d05eff0000 100644
--- a/src/Browser/Avalonia.Browser/BrowserTopLevelImpl.cs
+++ b/src/Browser/Avalonia.Browser/BrowserTopLevelImpl.cs
@@ -39,7 +39,6 @@ namespace Avalonia.Browser
         {
             Surfaces = Enumerable.Empty<object>();
             _avaloniaView = avaloniaView;
-            TransparencyLevel = WindowTransparencyLevel.None;
             AcrylicCompensationLevels = new AcrylicPlatformCompensationLevels(1, 1, 1);
             _touchDevice = new TouchDevice();
             _penDevice = new PenDevice();
@@ -187,12 +186,7 @@ namespace Avalonia.Browser
 
         }
 
-        public IRenderer CreateRenderer(IRenderRoot root)
-        {
-            var loop = AvaloniaLocator.Current.GetRequiredService<IRenderLoop>();
-            return new CompositingRenderer(root,
-                new Compositor(loop, AvaloniaLocator.Current.GetRequiredService<IPlatformGraphics>()), () => Surfaces);
-        }
+        public Compositor Compositor { get; } = new(AvaloniaLocator.Current.GetRequiredService<IPlatformGraphics>());
 
         public void Invalidate(Rect rect)
         {
@@ -223,13 +217,8 @@ namespace Avalonia.Browser
             return null;
         }
 
-        public void SetTransparencyLevelHint(WindowTransparencyLevel transparencyLevel)
+        public void SetTransparencyLevelHint(IReadOnlyList<WindowTransparencyLevel> transparencyLevel)
         {
-            if (transparencyLevel == WindowTransparencyLevel.None
-                || transparencyLevel == WindowTransparencyLevel.Transparent)
-            {
-                TransparencyLevel = transparencyLevel;
-            }
         }
 
         public Size ClientSize => _clientSize;
@@ -249,7 +238,7 @@ namespace Avalonia.Browser
         public IMouseDevice MouseDevice { get; } = new MouseDevice();
 
         public IKeyboardDevice KeyboardDevice { get; } = BrowserWindowingPlatform.Keyboard;
-        public WindowTransparencyLevel TransparencyLevel { get; private set; }
+        public WindowTransparencyLevel TransparencyLevel => WindowTransparencyLevel.None;
         public void SetFrameThemeVariant(PlatformThemeVariant themeVariant)
         {
             // not in the standard, but we potentially can use "apple-mobile-web-app-status-bar-style" for iOS and "theme-color" for android.
diff --git a/src/Browser/Avalonia.Browser/Interop/StorageHelper.cs b/src/Browser/Avalonia.Browser/Interop/StorageHelper.cs
index d95d4405ba..c28efbb308 100644
--- a/src/Browser/Avalonia.Browser/Interop/StorageHelper.cs
+++ b/src/Browser/Avalonia.Browser/Interop/StorageHelper.cs
@@ -39,6 +39,9 @@ internal static partial class StorageHelper
 
     [JSImport("StorageItem.openRead", AvaloniaModule.StorageModuleName)]
     public static partial Task<JSObject> OpenRead(JSObject item);
+    
+    [JSImport("StorageItem.createFromHandle", AvaloniaModule.StorageModuleName)]
+    public static partial JSObject? StorageItemFromHandle(JSObject handle);
 
     [JSImport("StorageItem.getItemsIterator", AvaloniaModule.StorageModuleName)]
     [return: JSMarshalAs<JSType.Object>]
diff --git a/src/Browser/Avalonia.Browser/Storage/BrowserStorageProvider.cs b/src/Browser/Avalonia.Browser/Storage/BrowserStorageProvider.cs
index a28fd4cbde..ef34826238 100644
--- a/src/Browser/Avalonia.Browser/Storage/BrowserStorageProvider.cs
+++ b/src/Browser/Avalonia.Browser/Storage/BrowserStorageProvider.cs
@@ -319,13 +319,14 @@ internal class JSStorageFolder : JSStorageItem, IStorageBookmarkFolder
             }
 
             var kind = storageItem.GetPropertyAsString("kind");
+            var item = StorageHelper.StorageItemFromHandle(storageItem)!;
             switch (kind)
             {
                 case "directory":
-                    yield return new JSStorageFolder(storageItem);
+                    yield return new JSStorageFolder(item);
                     break;
                 case "file":
-                    yield return new JSStorageFile(storageItem);
+                    yield return new JSStorageFile(item);
                     break;
             }
         }
diff --git a/src/Browser/Avalonia.Browser/WindowingPlatform.cs b/src/Browser/Avalonia.Browser/WindowingPlatform.cs
index a33738079c..3ad2620206 100644
--- a/src/Browser/Avalonia.Browser/WindowingPlatform.cs
+++ b/src/Browser/Avalonia.Browser/WindowingPlatform.cs
@@ -41,7 +41,6 @@ namespace Avalonia.Browser
                 .Bind<IKeyboardDevice>().ToConstant(s_keyboard)
                 .Bind<IPlatformSettings>().ToSingleton<BrowserPlatformSettings>()
                 .Bind<IPlatformThreadingInterface>().ToConstant(instance)
-                .Bind<IRenderLoop>().ToConstant(new RenderLoop())
                 .Bind<IRenderTimer>().ToConstant(ManualTriggerRenderTimer.Instance)
                 .Bind<IWindowingPlatform>().ToConstant(instance)
                 .Bind<IPlatformGraphics>().ToConstant(new BrowserSkiaGraphics())
diff --git a/src/Headless/Avalonia.Headless/AvaloniaHeadlessPlatform.cs b/src/Headless/Avalonia.Headless/AvaloniaHeadlessPlatform.cs
index 8202dab874..411cdd5a95 100644
--- a/src/Headless/Avalonia.Headless/AvaloniaHeadlessPlatform.cs
+++ b/src/Headless/Avalonia.Headless/AvaloniaHeadlessPlatform.cs
@@ -24,7 +24,7 @@ namespace Avalonia.Headless
                 var st = Stopwatch.StartNew();
                 _forceTick = () => tick(st.Elapsed);
 
-                var timer = new DispatcherTimer(DispatcherPriority.Render)
+                var timer = new DispatcherTimer(DispatcherPriority.UiThreadRender)
                 {
                     Interval = TimeSpan.FromSeconds(1.0 / _framesPerSecond),
                     Tag = "HeadlessRenderTimer"
@@ -69,11 +69,10 @@ namespace Avalonia.Headless
                 .Bind<IPlatformSettings>().ToSingleton<DefaultPlatformSettings>()
                 .Bind<IPlatformIconLoader>().ToSingleton<HeadlessIconLoaderStub>()
                 .Bind<IKeyboardDevice>().ToConstant(new KeyboardDevice())
-                .Bind<IRenderLoop>().ToConstant(new RenderLoop())
                 .Bind<IRenderTimer>().ToConstant(new RenderTimer(60))
                 .Bind<IWindowingPlatform>().ToConstant(new HeadlessWindowingPlatform())
                 .Bind<PlatformHotkeyConfiguration>().ToSingleton<PlatformHotkeyConfiguration>();
-            Compositor = new Compositor(AvaloniaLocator.Current.GetRequiredService<IRenderLoop>(), null);
+            Compositor = new Compositor( null);
         }
 
         /// <summary>
diff --git a/src/Headless/Avalonia.Headless/HeadlessPlatformRenderInterface.cs b/src/Headless/Avalonia.Headless/HeadlessPlatformRenderInterface.cs
index f99bebb5fe..7293874671 100644
--- a/src/Headless/Avalonia.Headless/HeadlessPlatformRenderInterface.cs
+++ b/src/Headless/Avalonia.Headless/HeadlessPlatformRenderInterface.cs
@@ -457,7 +457,7 @@ namespace Avalonia.Headless
 
             }
 
-            public void PushOpacity(double opacity, Rect rect)
+            public void PushOpacity(double opacity, Rect? rect)
             {
 
             }
diff --git a/src/Headless/Avalonia.Headless/HeadlessWindowImpl.cs b/src/Headless/Avalonia.Headless/HeadlessWindowImpl.cs
index 93f92d46f8..3f486d98f6 100644
--- a/src/Headless/Avalonia.Headless/HeadlessWindowImpl.cs
+++ b/src/Headless/Avalonia.Headless/HeadlessWindowImpl.cs
@@ -53,8 +53,7 @@ namespace Avalonia.Headless
         public Action<Size, WindowResizeReason>? Resized { get; set; }
         public Action<double>? ScalingChanged { get; set; }
 
-        public IRenderer CreateRenderer(IRenderRoot root) =>
-            new CompositingRenderer(root, AvaloniaHeadlessPlatform.Compositor!, () => Surfaces);
+        public Compositor Compositor => AvaloniaHeadlessPlatform.Compositor!;
 
         public void Invalidate(Rect rect)
         {
@@ -337,7 +336,7 @@ namespace Avalonia.Headless
             
         }
 
-        public void SetTransparencyLevelHint(WindowTransparencyLevel transparencyLevel)
+        public void SetTransparencyLevelHint(IReadOnlyList<WindowTransparencyLevel> transparencyLevel)
         {
             
         }
diff --git a/src/Linux/Avalonia.LinuxFramebuffer/FramebufferToplevelImpl.cs b/src/Linux/Avalonia.LinuxFramebuffer/FramebufferToplevelImpl.cs
index ccc8cab8ae..5843b5400e 100644
--- a/src/Linux/Avalonia.LinuxFramebuffer/FramebufferToplevelImpl.cs
+++ b/src/Linux/Avalonia.LinuxFramebuffer/FramebufferToplevelImpl.cs
@@ -32,10 +32,7 @@ using Avalonia.Rendering.Composition;
                 Dispatcher.UIThread.Post(() => _inputQueue.HandleEvent(e), DispatcherPriority.Send ));
         }
 
-        public IRenderer CreateRenderer(IRenderRoot root)
-        {
-            return new CompositingRenderer(root, LinuxFramebufferPlatform.Compositor, () => Surfaces);
-        }
+        public Compositor Compositor => LinuxFramebufferPlatform.Compositor;
 
         public void Dispose()
         {
@@ -75,9 +72,9 @@ using Avalonia.Rendering.Composition;
 
         public Size ScaledSize => _outputBackend.PixelSize.ToSize(RenderScaling);
 
-        public void SetTransparencyLevelHint(WindowTransparencyLevel transparencyLevel) { }
+        public void SetTransparencyLevelHint(IReadOnlyList<WindowTransparencyLevel> transparencyLevel) { }
 
-        public WindowTransparencyLevel TransparencyLevel { get; private set; }
+        public WindowTransparencyLevel TransparencyLevel => WindowTransparencyLevel.None;
 
         public void SetFrameThemeVariant(PlatformThemeVariant themeVariant) { }
 
diff --git a/src/Linux/Avalonia.LinuxFramebuffer/LinuxFramebufferPlatform.cs b/src/Linux/Avalonia.LinuxFramebuffer/LinuxFramebufferPlatform.cs
index c352b5f9bf..438e94b42e 100644
--- a/src/Linux/Avalonia.LinuxFramebuffer/LinuxFramebufferPlatform.cs
+++ b/src/Linux/Avalonia.LinuxFramebuffer/LinuxFramebufferPlatform.cs
@@ -45,15 +45,12 @@ namespace Avalonia.LinuxFramebuffer
             AvaloniaLocator.CurrentMutable
                 .Bind<IDispatcherImpl>().ToConstant(new ManagedDispatcherImpl(new ManualRawEventGrouperDispatchQueueDispatcherInputProvider(EventGrouperDispatchQueue)))
                 .Bind<IRenderTimer>().ToConstant(new DefaultRenderTimer(opts.Fps))
-                .Bind<IRenderLoop>().ToConstant(new RenderLoop())
                 .Bind<ICursorFactory>().ToTransient<CursorFactoryStub>()
                 .Bind<IKeyboardDevice>().ToConstant(new KeyboardDevice())
                 .Bind<IPlatformSettings>().ToSingleton<DefaultPlatformSettings>()
                 .Bind<PlatformHotkeyConfiguration>().ToSingleton<PlatformHotkeyConfiguration>();
             
-            Compositor = new Compositor(
-                AvaloniaLocator.Current.GetRequiredService<IRenderLoop>(),
-                AvaloniaLocator.Current.GetService<IPlatformGraphics>());
+            Compositor = new Compositor(AvaloniaLocator.Current.GetService<IPlatformGraphics>());
         }
 
 
@@ -69,7 +66,7 @@ namespace Avalonia.LinuxFramebuffer
     {
         private readonly IOutputBackend _fb;
         private readonly IInputBackend? _inputBackend;
-        private TopLevel? _topLevel;
+        private EmbeddableControlRoot? _topLevel;
         private readonly CancellationTokenSource _cts = new CancellationTokenSource();
         public CancellationToken Token => _cts.Token;
 
@@ -102,8 +99,9 @@ namespace Avalonia.LinuxFramebuffer
 
                     var tl = new EmbeddableControlRoot(new FramebufferToplevelImpl(_fb, inputBackend));
                     tl.Prepare();
+                    tl.StartRendering();
                     _topLevel = tl;
-                    _topLevel.Renderer.Start();
+                    
 
                     if (_topLevel is IFocusScope scope)
                     {
diff --git a/src/Linux/Avalonia.LinuxFramebuffer/Output/DrmBindings.cs b/src/Linux/Avalonia.LinuxFramebuffer/Output/DrmBindings.cs
index 070e1a95bc..850ea6d4a6 100644
--- a/src/Linux/Avalonia.LinuxFramebuffer/Output/DrmBindings.cs
+++ b/src/Linux/Avalonia.LinuxFramebuffer/Output/DrmBindings.cs
@@ -115,7 +115,7 @@ namespace Avalonia.LinuxFramebuffer.Output
 
         }
 
-        public void Dump()
+        internal void Dump()
         {
             void Print(int off, string s)
             {
diff --git a/src/Linux/Avalonia.LinuxFramebuffer/Output/DrmOutput.cs b/src/Linux/Avalonia.LinuxFramebuffer/Output/DrmOutput.cs
index 0135cb3d1f..c91498fe05 100644
--- a/src/Linux/Avalonia.LinuxFramebuffer/Output/DrmOutput.cs
+++ b/src/Linux/Avalonia.LinuxFramebuffer/Output/DrmOutput.cs
@@ -49,6 +49,7 @@ namespace Avalonia.LinuxFramebuffer.Output
                 _outputOptions = options;
             Init(card, resources, connector, modeInfo);
         }
+        
         public DrmOutput(string path = null, bool connectorsForceProbe = false, DrmOutputOptions options = null)
         {
             if(options != null) 
diff --git a/src/Markup/Avalonia.Markup.Xaml.Loader/AvaloniaXamlIlRuntimeCompiler.cs b/src/Markup/Avalonia.Markup.Xaml.Loader/AvaloniaXamlIlRuntimeCompiler.cs
index e3d154ffdd..e2aab7d685 100644
--- a/src/Markup/Avalonia.Markup.Xaml.Loader/AvaloniaXamlIlRuntimeCompiler.cs
+++ b/src/Markup/Avalonia.Markup.Xaml.Loader/AvaloniaXamlIlRuntimeCompiler.cs
@@ -231,8 +231,8 @@ namespace Avalonia.Markup.Xaml.XamlIl
                                ?? ((IXamlAstValueNode)parsed.Root).Type.GetClrType().Name;
                 var tb = _sreBuilder.DefineType("Builder_" + Guid.NewGuid().ToString("N") + "_" + xamlName);
                 var builder = _sreTypeSystem.CreateTypeBuilder(tb);
-                parsedDocuments.Add(new XamlDocumentResource(parsed, document.BaseUri?.ToString(), null, null,
-                    builder,
+                parsedDocuments.Add(new XamlDocumentResource(parsed, document.BaseUri?.ToString(),
+                    null, null, true, builder,
                     compiler.DefinePopulateMethod(builder, parsed, AvaloniaXamlIlCompiler.PopulateName, true),
                     document.RootInstance is null ? compiler.DefineBuildMethod(builder, parsed, AvaloniaXamlIlCompiler.BuildName, true) : null));
                 originalDocuments.Add(document);
diff --git a/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/AvaloniaXamlIlLanguageParseIntrinsics.cs b/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/AvaloniaXamlIlLanguageParseIntrinsics.cs
index 819e721b36..df1c4aa6d6 100644
--- a/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/AvaloniaXamlIlLanguageParseIntrinsics.cs
+++ b/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/AvaloniaXamlIlLanguageParseIntrinsics.cs
@@ -274,6 +274,19 @@ namespace Avalonia.Markup.Xaml.XamlIl.CompilerExtensions
                 }
             }
 
+            if (type.Equals(types.WindowTransparencyLevel))
+            {
+                foreach (var property in types.WindowTransparencyLevel.Properties)
+                {
+                    if (property.PropertyType == types.WindowTransparencyLevel && property.Name.Equals(text, StringComparison.OrdinalIgnoreCase))
+                    {
+                        result = new XamlStaticOrTargetedReturnMethodCallNode(node, property.Getter, Enumerable.Empty<IXamlAstValueNode>());
+
+                        return true;
+                    }
+                }
+            }
+
             if (type.Equals(types.Uri))
             {
                 var uriText = text.Trim();
@@ -385,7 +398,8 @@ namespace Avalonia.Markup.Xaml.XamlIl.CompilerExtensions
                     result = new AvaloniaXamlIlArrayConstantAstNode(node, elementType.MakeArrayType(1), elementType, nodes);
                     return true;
                 }
-                else if (type == context.Configuration.WellKnownTypes.IListOfT.MakeGenericType(elementType))
+                else if (type == context.Configuration.WellKnownTypes.IListOfT.MakeGenericType(elementType) ||
+                    type == types.IReadOnlyListOfT.MakeGenericType(elementType))
                 {
                     var listType = context.Configuration.WellKnownTypes.IListOfT.MakeGenericType(elementType);
                     result = new AvaloniaXamlIlArrayConstantAstNode(node, listType, elementType, nodes);
diff --git a/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/GroupTransformers/XamlIncludeGroupTransformer.cs b/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/GroupTransformers/XamlIncludeGroupTransformer.cs
index b6a4b599fa..28a48e5855 100644
--- a/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/GroupTransformers/XamlIncludeGroupTransformer.cs
+++ b/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/GroupTransformers/XamlIncludeGroupTransformer.cs
@@ -108,7 +108,7 @@ internal class AvaloniaXamlIncludeTransformer : IXamlAstGroupTransformer
         }
 
         var relativeName = "Build:" + assetPath.Substring(assemblyNameSeparator);
-        var buildMethod = avaResType.FindMethod(m => m.Name == relativeName);
+        var buildMethod = avaResType.FindMethod(m => m.Name == relativeName && m.IsPublic);
         if (buildMethod is not null)
         {
             return FromMethod(context, buildMethod, sourceUriNode, expectedLoadedType, node, assetPathUri, assembly, additionalProperties);
@@ -119,7 +119,7 @@ internal class AvaloniaXamlIncludeTransformer : IXamlAstGroupTransformer
         }
 
         return context.ParseError(
-            $"Unable to resolve XAML resource \"{assetPathUri}\" in the \"{assembly}\" assembly.",
+            $"Unable to resolve XAML resource \"{assetPathUri}\" in the \"{assembly}\" assembly. Make sure this file exists and is public.",
             sourceUriNode, node);
     }
 
diff --git a/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/Transformers/AvaloniaXamlIlWellKnownTypes.cs b/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/Transformers/AvaloniaXamlIlWellKnownTypes.cs
index d160d4a277..05fe4bd2b8 100644
--- a/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/Transformers/AvaloniaXamlIlWellKnownTypes.cs
+++ b/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/Transformers/AvaloniaXamlIlWellKnownTypes.cs
@@ -117,6 +117,8 @@ namespace Avalonia.Markup.Xaml.XamlIl.CompilerExtensions.Transformers
         public IXamlConstructor UriConstructor { get; }
         public IXamlType Style { get; }
         public IXamlType ControlTheme { get; }
+        public IXamlType WindowTransparencyLevel { get; }
+        public IXamlType IReadOnlyListOfT { get; }
 
         public AvaloniaXamlIlWellKnownTypes(TransformerConfiguration cfg)
         {
@@ -199,6 +201,7 @@ namespace Avalonia.Markup.Xaml.XamlIl.CompilerExtensions.Transformers
             FontFamily = cfg.TypeSystem.GetType("Avalonia.Media.FontFamily");
             FontFamilyConstructorUriName = FontFamily.GetConstructor(new List<IXamlType> { Uri, XamlIlTypes.String });
             ThemeVariant = cfg.TypeSystem.GetType("Avalonia.Styling.ThemeVariant");
+            WindowTransparencyLevel = cfg.TypeSystem.GetType("Avalonia.Controls.WindowTransparencyLevel");
 
             (IXamlType, IXamlConstructor) GetNumericTypeInfo(string name, IXamlType componentType, int componentCount)
             {
@@ -260,6 +263,7 @@ namespace Avalonia.Markup.Xaml.XamlIl.CompilerExtensions.Transformers
             UriConstructor = Uri.GetConstructor(new List<IXamlType>() { cfg.WellKnownTypes.String, UriKind });
             Style = cfg.TypeSystem.GetType("Avalonia.Styling.Style");
             ControlTheme = cfg.TypeSystem.GetType("Avalonia.Styling.ControlTheme");
+            IReadOnlyListOfT = cfg.TypeSystem.GetType("System.Collections.Generic.IReadOnlyList`1");
         }
     }
 
diff --git a/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/XamlDocumentResource.cs b/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/XamlDocumentResource.cs
index d5d452a9f3..932fe067af 100644
--- a/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/XamlDocumentResource.cs
+++ b/src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/XamlDocumentResource.cs
@@ -13,6 +13,7 @@ internal class XamlDocumentResource : IXamlDocumentResource
         string? uri,
         IFileSource? fileSource,
         IXamlType? classType,
+        bool isPublic,
         IXamlTypeBuilder<IXamlILEmitter> typeBuilder,
         IXamlMethodBuilder<IXamlILEmitter> populateMethod,
         IXamlMethodBuilder<IXamlILEmitter>? buildMethod)
@@ -21,6 +22,7 @@ internal class XamlDocumentResource : IXamlDocumentResource
         Uri = uri;
         FileSource = fileSource;
         ClassType = classType;
+        IsPublic = isPublic;
         TypeBuilder = typeBuilder;
         PopulateMethod = populateMethod;
         BuildMethod = buildMethod;
@@ -31,6 +33,7 @@ internal class XamlDocumentResource : IXamlDocumentResource
     public IFileSource? FileSource { get; }
 
     public IXamlType? ClassType { get; }
+    public bool IsPublic { get; }
     public IXamlTypeBuilder<IXamlILEmitter> TypeBuilder { get; }
     public IXamlMethodBuilder<IXamlILEmitter> PopulateMethod { get; }
     public IXamlMethodBuilder<IXamlILEmitter>? BuildMethod { get; }
diff --git a/src/Skia/Avalonia.Skia/DrawingContextImpl.cs b/src/Skia/Avalonia.Skia/DrawingContextImpl.cs
index f74ba179c1..fbff4ab4e7 100644
--- a/src/Skia/Avalonia.Skia/DrawingContextImpl.cs
+++ b/src/Skia/Avalonia.Skia/DrawingContextImpl.cs
@@ -588,14 +588,21 @@ namespace Avalonia.Skia
         }
 
         /// <inheritdoc />
-        public void PushOpacity(double opacity, Rect bounds)
+        public void PushOpacity(double opacity, Rect? bounds)
         {
             CheckLease();
 
             if(_useOpacitySaveLayer)
             {
-                var rect = bounds.ToSKRect();
-                Canvas.SaveLayer(rect, new SKPaint { ColorF = new SKColorF(0, 0, 0, (float)opacity)});
+                if (bounds.HasValue)
+                {
+                    var rect = bounds.Value.ToSKRect();
+                    Canvas.SaveLayer(rect, new SKPaint { ColorF = new SKColorF(0, 0, 0, (float)opacity) });
+                }
+                else
+                {
+                    Canvas.SaveLayer(new SKPaint { ColorF = new SKColorF(0, 0, 0, (float)opacity) });
+                }
             }
             else
             {
diff --git a/src/Windows/Avalonia.Direct2D1/Avalonia.Direct2D1.csproj b/src/Windows/Avalonia.Direct2D1/Avalonia.Direct2D1.csproj
index bbe2a92074..78da843f42 100644
--- a/src/Windows/Avalonia.Direct2D1/Avalonia.Direct2D1.csproj
+++ b/src/Windows/Avalonia.Direct2D1/Avalonia.Direct2D1.csproj
@@ -18,6 +18,7 @@
     <InternalsVisibleTo Include="Avalonia.Direct2D1.RenderTests, PublicKey=$(AvaloniaPublicKey)" />
     <InternalsVisibleTo Include="Avalonia.Direct2D1.UnitTests, PublicKey=$(AvaloniaPublicKey)" />
     <InternalsVisibleTo Include="Avalonia.Win32.Interoperability, PublicKey=$(AvaloniaPublicKey)"/>
+    <InternalsVisibleTo Include="Avalonia.Win32.Interop, PublicKey=$(AvaloniaPublicKey)" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/src/Windows/Avalonia.Direct2D1/Direct2DChecker.cs b/src/Windows/Avalonia.Direct2D1/Direct2DChecker.cs
deleted file mode 100644
index d1233ca4e7..0000000000
--- a/src/Windows/Avalonia.Direct2D1/Direct2DChecker.cs
+++ /dev/null
@@ -1,24 +0,0 @@
-using Avalonia.Platform;
-
-namespace Avalonia.Direct2D1
-{
-    class Direct2DChecker : IModuleEnvironmentChecker
-    {
-        //Direct2D backend doesn't work on some machines anymore
-        public bool IsCompatible
-        {
-            get
-            {
-                try
-                {
-                    Direct2D1Platform.InitializeDirect2D();
-                    return true;
-                }
-                catch
-                {
-                    return false;
-                }
-            }
-        }
-    }
-}
diff --git a/src/Windows/Avalonia.Direct2D1/Media/DrawingContextImpl.cs b/src/Windows/Avalonia.Direct2D1/Media/DrawingContextImpl.cs
index 407fadb9f5..5579278f21 100644
--- a/src/Windows/Avalonia.Direct2D1/Media/DrawingContextImpl.cs
+++ b/src/Windows/Avalonia.Direct2D1/Media/DrawingContextImpl.cs
@@ -454,17 +454,26 @@ namespace Avalonia.Direct2D1.Media
         /// <param name="opacity">The opacity.</param>
         /// <param name="bounds">The bounds.</param>
         /// <returns>A disposable used to undo the opacity.</returns>
-        public void PushOpacity(double opacity, Rect bounds)
+        public void PushOpacity(double opacity, Rect? bounds)
         {
             if (opacity < 1)
             {
+                if(bounds == null || bounds == default(Rect))
+                {
+                    bounds = new Rect(0, 0, _renderTarget.PixelSize.Width, _renderTarget.PixelSize.Height);
+                }
+
                 var parameters = new LayerParameters
                 {
-                    ContentBounds = bounds.ToDirect2D(),
                     MaskTransform = PrimitiveExtensions.Matrix3x2Identity,
-                    Opacity = (float)opacity,
+                    Opacity = (float)opacity
                 };
 
+                if(bounds.HasValue)
+                {
+                    parameters.ContentBounds = bounds.Value.ToDirect2D();
+                }
+
                 var layer = _layerPool.Count != 0 ? _layerPool.Pop() : new Layer(_deviceContext);
                 _deviceContext.PushLayer(ref parameters, layer);
 
diff --git a/src/Windows/Avalonia.Win32.Interoperability/Avalonia.Win32.Interoperability.csproj b/src/Windows/Avalonia.Win32.Interoperability/Avalonia.Win32.Interoperability.csproj
index bf1e83fb66..cc1dfb385c 100644
--- a/src/Windows/Avalonia.Win32.Interoperability/Avalonia.Win32.Interoperability.csproj
+++ b/src/Windows/Avalonia.Win32.Interoperability/Avalonia.Win32.Interoperability.csproj
@@ -5,6 +5,10 @@
     <UseWpf>true</UseWpf>
     <UseWindowsForms>true</UseWindowsForms>
     <EnableWindowsTargeting>true</EnableWindowsTargeting>
+    <ExtrasEnableImplicitWinFormsReferences>true</ExtrasEnableImplicitWinFormsReferences>
+    <EnableWindowsTargeting>true</EnableWindowsTargeting>
+    <UseDirect3D9>true</UseDirect3D9>
+    <PackageId>Avalonia.Win32.Interoperability</PackageId>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/src/Windows/Avalonia.Win32/Interop/UnmanagedMethods.cs b/src/Windows/Avalonia.Win32/Interop/UnmanagedMethods.cs
index 7510b48270..39363beae3 100644
--- a/src/Windows/Avalonia.Win32/Interop/UnmanagedMethods.cs
+++ b/src/Windows/Avalonia.Win32/Interop/UnmanagedMethods.cs
@@ -1909,7 +1909,7 @@ namespace Avalonia.Win32.Interop
                     var result = ImmGetCompositionString(hIMC, dwIndex, (IntPtr)bufferPtr, (uint)bufferLength);
                     if (result >= 0)
                     {
-                        return Marshal.PtrToStringUni((IntPtr)bufferPtr);
+                        return Encoding.Unicode.GetString(bufferPtr, result);
                     }
                 }
             }
diff --git a/src/Windows/Avalonia.Win32/PlatformConstants.cs b/src/Windows/Avalonia.Win32/PlatformConstants.cs
index 48dd9f45da..bed78501f3 100644
--- a/src/Windows/Avalonia.Win32/PlatformConstants.cs
+++ b/src/Windows/Avalonia.Win32/PlatformConstants.cs
@@ -2,12 +2,13 @@ using System;
 
 namespace Avalonia.Win32
 {
-    public static class PlatformConstants
+    internal static class PlatformConstants
     {
         public const string WindowHandleType = "HWND";
         public const string CursorHandleType = "HCURSOR";
 
-        internal static readonly Version Windows8 = new Version(6, 2);
-        internal static readonly Version Windows7 = new Version(6, 1);
+        public static readonly Version Windows10 = new Version(10, 0);
+        public static readonly Version Windows8 = new Version(6, 2);
+        public static readonly Version Windows7 = new Version(6, 1);
     }
 }
diff --git a/src/Windows/Avalonia.Win32/TrayIconImpl.cs b/src/Windows/Avalonia.Win32/TrayIconImpl.cs
index 5069add9fd..f2023d37ac 100644
--- a/src/Windows/Avalonia.Win32/TrayIconImpl.cs
+++ b/src/Windows/Avalonia.Win32/TrayIconImpl.cs
@@ -147,7 +147,7 @@ namespace Avalonia.Win32
                 SystemDecorations = SystemDecorations.None,
                 SizeToContent = SizeToContent.WidthAndHeight,
                 Background = null,
-                TransparencyLevelHint = WindowTransparencyLevel.Transparent,
+                TransparencyLevelHint = new[] { WindowTransparencyLevel.Transparent },
                 Content = new TrayIconMenuFlyoutPresenter()
                 {
                     ItemsSource = menuItems
diff --git a/src/Windows/Avalonia.Win32/Win32Platform.cs b/src/Windows/Avalonia.Win32/Win32Platform.cs
index 7ce599c6bf..e9019803be 100644
--- a/src/Windows/Avalonia.Win32/Win32Platform.cs
+++ b/src/Windows/Avalonia.Win32/Win32Platform.cs
@@ -159,7 +159,6 @@ namespace Avalonia.Win32
                 .Bind<IKeyboardDevice>().ToConstant(WindowsKeyboardDevice.Instance)
                 .Bind<IPlatformSettings>().ToSingleton<Win32PlatformSettings>()
                 .Bind<IDispatcherImpl>().ToConstant(s_instance._dispatcher)
-                .Bind<IRenderLoop>().ToConstant(new RenderLoop())
                 .Bind<IRenderTimer>().ToConstant(renderTimer)
                 .Bind<IWindowingPlatform>().ToConstant(s_instance)
                 .Bind<PlatformHotkeyConfiguration>().ToConstant(new PlatformHotkeyConfiguration(KeyModifiers.Control)
@@ -181,7 +180,7 @@ namespace Avalonia.Win32
             if (OleContext.Current != null)
                 AvaloniaLocator.CurrentMutable.Bind<IPlatformDragSource>().ToSingleton<DragSource>();
             
-            s_compositor = new Compositor(AvaloniaLocator.Current.GetRequiredService<IRenderLoop>(), platformGraphics);
+            s_compositor = new Compositor( platformGraphics);
         }
         
         public event EventHandler<ShutdownRequestedEventArgs>? ShutdownRequested;
diff --git a/src/Windows/Avalonia.Win32/WinRT/Composition/WinUiCompositionShared.cs b/src/Windows/Avalonia.Win32/WinRT/Composition/WinUiCompositionShared.cs
index 602d0a3f8a..f17805fba3 100644
--- a/src/Windows/Avalonia.Win32/WinRT/Composition/WinUiCompositionShared.cs
+++ b/src/Windows/Avalonia.Win32/WinRT/Composition/WinUiCompositionShared.cs
@@ -12,6 +12,7 @@ internal class WinUiCompositionShared : IDisposable
     public ICompositionBrush? MicaBrush { get; }
     public object SyncRoot { get; } = new();
 
+    public static readonly Version MinAcrylicVersion = new(10, 0, 15063);
     public static readonly Version MinHostBackdropVersion = new(10, 0, 22000);
     
     public WinUiCompositionShared(ICompositor compositor)
diff --git a/src/Windows/Avalonia.Win32/WindowImpl.AppWndProc.cs b/src/Windows/Avalonia.Win32/WindowImpl.AppWndProc.cs
index 2a3255bb70..b256a9433d 100644
--- a/src/Windows/Avalonia.Win32/WindowImpl.AppWndProc.cs
+++ b/src/Windows/Avalonia.Win32/WindowImpl.AppWndProc.cs
@@ -594,7 +594,6 @@ namespace Avalonia.Win32
                 case WindowsMessage.WM_PAINT:
                     {
                         using (NonPumpingSyncContext.Use(NonPumpingWaitHelperImpl.Instance))
-                        using (_rendererLock.Lock())
                         {
                             if (BeginPaint(_hwnd, out PAINTSTRUCT ps) != IntPtr.Zero)
                             {
@@ -616,12 +615,6 @@ namespace Avalonia.Win32
 
                 case WindowsMessage.WM_SIZE:
                     {
-                        using (NonPumpingSyncContext.Use(NonPumpingWaitHelperImpl.Instance))
-                        using (_rendererLock.Lock())
-                        {
-                            // Do nothing here, just block until the pending frame render is completed on the render thread
-                        }
-
                         var size = (SizeCommand)wParam;
 
                         if (Resized != null &&
@@ -837,11 +830,8 @@ namespace Avalonia.Win32
                     return IntPtr.Zero;
                 }
             }
-
-            using (_rendererLock.Lock())
-            {
-                return DefWindowProc(hWnd, msg, wParam, lParam);
-            }
+            
+            return DefWindowProc(hWnd, msg, wParam, lParam);
         }
 
         private Lazy<IReadOnlyList<RawPointerPoint>?>? CreateLazyIntermediatePoints(POINTER_INFO info)
diff --git a/src/Windows/Avalonia.Win32/WindowImpl.CustomCaptionProc.cs b/src/Windows/Avalonia.Win32/WindowImpl.CustomCaptionProc.cs
index 4a4565a443..7c5aff8b75 100644
--- a/src/Windows/Avalonia.Win32/WindowImpl.CustomCaptionProc.cs
+++ b/src/Windows/Avalonia.Win32/WindowImpl.CustomCaptionProc.cs
@@ -1,6 +1,7 @@
 using System;
 using Avalonia.Controls;
 using Avalonia.Input;
+using Avalonia.VisualTree;
 using static Avalonia.Win32.Interop.UnmanagedMethods;
 
 namespace Avalonia.Win32
@@ -105,7 +106,7 @@ namespace Avalonia.Win32
 
                             if (_owner is Window window)
                             {
-                                var visual = window.Renderer.HitTestFirst(position, window, x =>
+                                var visual = window.GetVisualAt(position, x =>
                                 {
                                     if (x is IInputElement ie && (!ie.IsHitTestVisible || !ie.IsEffectivelyVisible))
                                     {
diff --git a/src/Windows/Avalonia.Win32/WindowImpl.cs b/src/Windows/Avalonia.Win32/WindowImpl.cs
index 9217f42952..4260f90e9f 100644
--- a/src/Windows/Avalonia.Win32/WindowImpl.cs
+++ b/src/Windows/Avalonia.Win32/WindowImpl.cs
@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Diagnostics.CodeAnalysis;
@@ -25,6 +25,7 @@ using Avalonia.Win32.WinRT.Composition;
 using Avalonia.Win32.WinRT;
 using static Avalonia.Win32.Interop.UnmanagedMethods;
 using Avalonia.Input.Platform;
+using System.Diagnostics;
 
 namespace Avalonia.Win32
 {
@@ -70,7 +71,6 @@ namespace Avalonia.Win32
         private readonly TouchDevice _touchDevice;
         private readonly WindowsMouseDevice _mouseDevice;
         private readonly PenDevice _penDevice;
-        private readonly ManagedDeferredRendererLock _rendererLock;
         private readonly FramebufferManager _framebuffer;
         private readonly object? _gl;
         private readonly bool _wmPointerEnabled;
@@ -98,6 +98,7 @@ namespace Avalonia.Win32
         private bool _hiddenWindowIsParent;
         private uint _langid;
         private bool _ignoreWmChar;
+        private WindowTransparencyLevel _transparencyLevel;
 
         private const int MaxPointerHistorySize = 512;
         private static readonly PooledList<RawPointerPoint> s_intermediatePointsPooledList = new();
@@ -128,7 +129,6 @@ namespace Avalonia.Win32
                 IsResizable = true,
                 Decorations = SystemDecorations.Full
             };
-            _rendererLock = new ManagedDeferredRendererLock();
 
             var glPlatform = AvaloniaLocator.Current.GetService<IPlatformGraphics>();
 
@@ -182,6 +182,7 @@ namespace Avalonia.Win32
             _storageProvider = new Win32StorageProvider(this);
 
             _nativeControlHost = new Win32NativeControlHost(this, _isUsingComposition);
+            _transparencyLevel = _isUsingComposition ? WindowTransparencyLevel.Transparent : WindowTransparencyLevel.None;
             s_instances.Add(this);
         }
 
@@ -315,7 +316,18 @@ namespace Avalonia.Win32
             }
         }
 
-        public WindowTransparencyLevel TransparencyLevel { get; private set; }
+        public WindowTransparencyLevel TransparencyLevel
+        {
+            get => _transparencyLevel;
+            private set
+            {
+                if (_transparencyLevel != value)
+                {
+                    _transparencyLevel = value;
+                    TransparencyLevelChanged?.Invoke(value);
+                }
+            }
+        }
 
         protected IntPtr Hwnd => _hwnd;
 
@@ -346,82 +358,132 @@ namespace Avalonia.Win32
             return null;
         }
 
-        public void SetTransparencyLevelHint(WindowTransparencyLevel transparencyLevel)
+        public void SetTransparencyLevelHint(IReadOnlyList<WindowTransparencyLevel> transparencyLevels)
         {
-            TransparencyLevel = EnableBlur(transparencyLevel);
-        }
+            var windowsVersion = Win32Platform.WindowsVersion;
+
+            foreach (var level in transparencyLevels)
+            {
+                if (!IsSupported(level, windowsVersion))
+                    continue;
+                if (level == TransparencyLevel)
+                    return;
+                if (level == WindowTransparencyLevel.Transparent)
+                    SetTransparencyTransparent(windowsVersion);
+                else if (level == WindowTransparencyLevel.Blur)
+                    SetTransparencyBlur(windowsVersion);
+                else if (level == WindowTransparencyLevel.AcrylicBlur)
+                    SetTransparencyAcrylicBlur(windowsVersion);
+                else if (level == WindowTransparencyLevel.Mica)
+                    SetTransparencyMica(windowsVersion);
+
+                TransparencyLevel = level;
+                return;
+            }
 
-        private WindowTransparencyLevel EnableBlur(WindowTransparencyLevel transparencyLevel)
-        {
-            if (Win32Platform.WindowsVersion.Major >= 6)
+            // If we get here, we didn't find a supported level. Use the defualt of Transparent or
+            // None, depending on whether composition is enabled.
+            if (_isUsingComposition)
             {
-                if (DwmIsCompositionEnabled(out var compositionEnabled) != 0 || !compositionEnabled)
-                {
-                    return WindowTransparencyLevel.None;
-                }
-                else if (Win32Platform.WindowsVersion.Major >= 10)
-                {
-                    return Win10EnableBlur(transparencyLevel);
-                }
-                else if (Win32Platform.WindowsVersion.Minor >= 2)
-                {
-                    return Win8xEnableBlur(transparencyLevel);
-                }
-                else
-                {
-                    return Win7EnableBlur(transparencyLevel);
-                }
+                SetTransparencyTransparent(windowsVersion);
+                TransparencyLevel = WindowTransparencyLevel.Transparent;
             }
             else
             {
-                return WindowTransparencyLevel.None;
+                TransparencyLevel = WindowTransparencyLevel.None;
             }
         }
 
-        private WindowTransparencyLevel Win7EnableBlur(WindowTransparencyLevel transparencyLevel)
+        private bool IsSupported(WindowTransparencyLevel level, Version windowsVersion)
         {
-            if (transparencyLevel == WindowTransparencyLevel.AcrylicBlur)
-            {
-                transparencyLevel = WindowTransparencyLevel.Blur;
-            }
+            // Only None is suppported when composition is disabled.
+            if (!_isUsingComposition)
+                return level == WindowTransparencyLevel.None;
 
-            var blurInfo = new DWM_BLURBEHIND(false);
+            // When composition is enabled, None is not supported because the backing visual always
+            // has an alpha channel
+            if (level == WindowTransparencyLevel.None)
+                return false;
 
-            if (transparencyLevel == WindowTransparencyLevel.Blur)
+            // Transparent only supported on Windows 8+.
+            if (level == WindowTransparencyLevel.Transparent)
+                return windowsVersion >= PlatformConstants.Windows8;
+
+            // Blur only supported on Windows 8 and lower.
+            if (level == WindowTransparencyLevel.Blur)
+                return windowsVersion < PlatformConstants.Windows10;
+
+            // Acrylic is supported on Windows >= 10.0.15063.
+            if (level == WindowTransparencyLevel.AcrylicBlur)
+                return windowsVersion >= WinUiCompositionShared.MinAcrylicVersion;
+
+            // Mica is supported on Windows >= 10.0.22000.
+            if (level == WindowTransparencyLevel.Mica)
+                return windowsVersion >= WinUiCompositionShared.MinHostBackdropVersion;
+
+            return false;
+        }
+
+        private void SetTransparencyTransparent(Version windowsVersion)
+        {
+            // Transparent only supported with composition on Windows 8+.
+            if (!_isUsingComposition || windowsVersion < PlatformConstants.Windows8)
+                return;
+
+            if (windowsVersion < PlatformConstants.Windows10)
             {
-                blurInfo = new DWM_BLURBEHIND(true);
+                // Some of the AccentState Enum's values have different meanings on Windows 8.x than on
+                // Windows 10, hence using ACCENT_ENABLE_BLURBEHIND to disable blurbehind  ¯\_(ツ)_/¯.
+                // Hey, I'm just porting what was here before.
+                SetAccentState(AccentState.ACCENT_ENABLE_BLURBEHIND);
+                var blurInfo = new DWM_BLURBEHIND(false);
+                DwmEnableBlurBehindWindow(_hwnd, ref blurInfo);
             }
 
+            SetUseHostBackdropBrush(false);
+            _blurHost?.SetBlur(BlurEffect.None);
+        }
+
+        private void SetTransparencyBlur(Version windowsVersion)
+        {
+            // Blur only supported with composition on Windows 8 and lower.
+            if (!_isUsingComposition || windowsVersion >= PlatformConstants.Windows10)
+                return;
+
+            // Some of the AccentState Enum's values have different meanings on Windows 8.x than on
+            // Windows 10.
+            SetAccentState(AccentState.ACCENT_DISABLED);
+            var blurInfo = new DWM_BLURBEHIND(true);
             DwmEnableBlurBehindWindow(_hwnd, ref blurInfo);
+        }
 
-            if (transparencyLevel == WindowTransparencyLevel.Transparent)
-            {
-                return WindowTransparencyLevel.None;
-            }
-            else
-            {
-                return transparencyLevel;
-            }
+        private void SetTransparencyAcrylicBlur(Version windowsVersion)
+        {
+            // Acrylic blur only supported with composition on Windows >= 10.0.15063.
+            if (!_isUsingComposition || windowsVersion < WinUiCompositionShared.MinAcrylicVersion)
+                return;
+
+            SetUseHostBackdropBrush(true);
+            _blurHost?.SetBlur(BlurEffect.Acrylic);
         }
 
-        private WindowTransparencyLevel Win8xEnableBlur(WindowTransparencyLevel transparencyLevel)
+        private void SetTransparencyMica(Version windowsVersion)
         {
-            var accent = new AccentPolicy();
-            var accentStructSize = Marshal.SizeOf<AccentPolicy>();
+            // Mica only supported with composition on Windows >= 10.0.22000.
+            if (!_isUsingComposition || windowsVersion < WinUiCompositionShared.MinHostBackdropVersion)
+                return;
 
-            if (transparencyLevel == WindowTransparencyLevel.AcrylicBlur)
-            {
-                transparencyLevel = WindowTransparencyLevel.Blur;
-            }
+            SetUseHostBackdropBrush(false);
+            _blurHost?.SetBlur(BlurEffect.Mica);
+        }
 
-            if (transparencyLevel == WindowTransparencyLevel.Transparent)
-            {
-                accent.AccentState = AccentState.ACCENT_ENABLE_BLURBEHIND;
-            }
-            else
-            {
-                accent.AccentState = AccentState.ACCENT_DISABLED;
-            }
+        private void SetAccentState(AccentState state)
+        {
+            var accent = new AccentPolicy();
+            var accentStructSize = Marshal.SizeOf(accent);
+
+            //Some of the AccentState Enum's values have different meanings on Windows 8.x than on Windows 10
+            accent.AccentState = state;
 
             var accentPtr = Marshal.AllocHGlobal(accentStructSize);
             Marshal.StructureToPtr(accent, accentPtr, false);
@@ -432,98 +494,18 @@ namespace Avalonia.Win32
             data.Data = accentPtr;
 
             SetWindowCompositionAttribute(_hwnd, ref data);
-
             Marshal.FreeHGlobal(accentPtr);
-
-            if (transparencyLevel >= WindowTransparencyLevel.Blur)
-            {
-                Win7EnableBlur(transparencyLevel);
-            }
-
-            return transparencyLevel;
         }
 
-        private WindowTransparencyLevel Win10EnableBlur(WindowTransparencyLevel transparencyLevel)
+        private void SetUseHostBackdropBrush(bool useHostBackdropBrush)
         {
-            if (_isUsingComposition)
-            {
-                var effect = transparencyLevel switch
-                {
-                    WindowTransparencyLevel.Mica => BlurEffect.Mica,
-                    WindowTransparencyLevel.AcrylicBlur => BlurEffect.Acrylic,
-                    WindowTransparencyLevel.Blur => BlurEffect.Acrylic,
-                    _ => BlurEffect.None
-                };
-
-                if (Win32Platform.WindowsVersion >= WinUiCompositionShared.MinHostBackdropVersion)
-                {
-                    unsafe
-                    {
-                        int pvUseBackdropBrush = effect == BlurEffect.Acrylic ? 1 : 0;
-                        DwmSetWindowAttribute(_hwnd, (int)DwmWindowAttribute.DWMWA_USE_HOSTBACKDROPBRUSH, &pvUseBackdropBrush, sizeof(int));
-                    }
-                }
-
-                if (Win32Platform.WindowsVersion < WinUiCompositionShared.MinHostBackdropVersion && effect == BlurEffect.Mica)
-                {
-                    effect = BlurEffect.Acrylic;
-                }
-
-                _blurHost?.SetBlur(effect);
+            if (Win32Platform.WindowsVersion < WinUiCompositionShared.MinHostBackdropVersion)
+                return;
 
-                return transparencyLevel;
-            }
-            else
+            unsafe
             {
-                bool canUseAcrylic = Win32Platform.WindowsVersion.Major > 10 || Win32Platform.WindowsVersion.Build >= 19628;
-
-                var accent = new AccentPolicy();
-                var accentStructSize = Marshal.SizeOf<AccentPolicy>();
-
-                if (transparencyLevel == WindowTransparencyLevel.AcrylicBlur && !canUseAcrylic)
-                {
-                    transparencyLevel = WindowTransparencyLevel.Blur;
-                }
-
-                switch (transparencyLevel)
-                {
-                    default:
-                    case WindowTransparencyLevel.None:
-                        accent.AccentState = AccentState.ACCENT_DISABLED;
-                        break;
-
-                    case WindowTransparencyLevel.Transparent:
-                        accent.AccentState = AccentState.ACCENT_ENABLE_TRANSPARENTGRADIENT;
-                        break;
-
-                    case WindowTransparencyLevel.Blur:
-                        accent.AccentState = AccentState.ACCENT_ENABLE_BLURBEHIND;
-                        break;
-
-                    case WindowTransparencyLevel.AcrylicBlur:
-                    case WindowTransparencyLevel.ForceAcrylicBlur: // hack-force acrylic.
-                    case WindowTransparencyLevel.Mica:
-                        accent.AccentState = AccentState.ACCENT_ENABLE_ACRYLIC;
-                        transparencyLevel = WindowTransparencyLevel.AcrylicBlur;
-                        break;
-                }
-
-                accent.AccentFlags = 2;
-                accent.GradientColor = 0x01000000;
-
-                var accentPtr = Marshal.AllocHGlobal(accentStructSize);
-                Marshal.StructureToPtr(accent, accentPtr, false);
-
-                var data = new WindowCompositionAttributeData();
-                data.Attribute = WindowCompositionAttribute.WCA_ACCENT_POLICY;
-                data.SizeOfData = accentStructSize;
-                data.Data = accentPtr;
-
-                SetWindowCompositionAttribute(_hwnd, ref data);
-
-                Marshal.FreeHGlobal(accentPtr);
-
-                return transparencyLevel;
+                var pvUseBackdropBrush = useHostBackdropBrush ? 1 : 0;
+                DwmSetWindowAttribute(_hwnd, (int)DwmWindowAttribute.DWMWA_USE_HOSTBACKDROPBRUSH, &pvUseBackdropBrush, sizeof(int));
             }
         }
 
@@ -585,8 +567,7 @@ namespace Avalonia.Win32
             _maxSize = maxSize;
         }
 
-        public IRenderer CreateRenderer(IRenderRoot root) =>
-            new CompositingRenderer(root, Win32Platform.Compositor, () => Surfaces);
+        public Compositor Compositor => Win32Platform.Compositor;
 
         public void Resize(Size value, WindowResizeReason reason)
         {
@@ -1498,7 +1479,7 @@ namespace Avalonia.Win32
             public void Dispose() => _owner._resizeReason = _restore;
         }
 
-        private class WindowImplPlatformHandle : IPlatformNativeSurfaceHandle
+        private class WindowImplPlatformHandle : INativePlatformHandleSurface
         {
             private readonly WindowImpl _owner;
             public WindowImplPlatformHandle(WindowImpl owner) => _owner = owner;
diff --git a/src/iOS/Avalonia.iOS/AvaloniaView.cs b/src/iOS/Avalonia.iOS/AvaloniaView.cs
index 6ca0cf7ace..74cabb294d 100644
--- a/src/iOS/Avalonia.iOS/AvaloniaView.cs
+++ b/src/iOS/Avalonia.iOS/AvaloniaView.cs
@@ -38,7 +38,7 @@ namespace Avalonia.iOS
 
             _topLevel.Prepare();
 
-            _topLevel.Renderer.Start();
+            _topLevel.StartRendering();
 
             var l = (CAEAGLLayer)Layer;
             l.ContentsScale = UIScreen.MainScreen.Scale;
@@ -110,9 +110,7 @@ namespace Avalonia.iOS
                 // No-op
             }
 
-            public IRenderer CreateRenderer(IRenderRoot root) =>
-                new CompositingRenderer(root, Platform.Compositor, () => Surfaces);
-
+            public Compositor Compositor => Platform.Compositor;
 
             public void Invalidate(Rect rect)
             {
@@ -139,7 +137,7 @@ namespace Avalonia.iOS
                 return null;
             }
 
-            public void SetTransparencyLevelHint(WindowTransparencyLevel transparencyLevel)
+            public void SetTransparencyLevelHint(IReadOnlyList<WindowTransparencyLevel> transparencyLevel)
             {
                 // No-op
             }
@@ -159,8 +157,8 @@ namespace Avalonia.iOS
 
             // legacy no-op
             public IMouseDevice MouseDevice { get; } = new MouseDevice();
-            public WindowTransparencyLevel TransparencyLevel { get; }
-            
+            public WindowTransparencyLevel TransparencyLevel => WindowTransparencyLevel.None;
+
             public void SetFrameThemeVariant(PlatformThemeVariant themeVariant)
             {
                 // TODO adjust status bar depending on full screen mode.
diff --git a/src/iOS/Avalonia.iOS/Platform.cs b/src/iOS/Avalonia.iOS/Platform.cs
index cf5c89cf5f..de664c93e0 100644
--- a/src/iOS/Avalonia.iOS/Platform.cs
+++ b/src/iOS/Avalonia.iOS/Platform.cs
@@ -43,17 +43,12 @@ namespace Avalonia.iOS
                 .Bind<IPlatformSettings>().ToSingleton<PlatformSettings>()
                 .Bind<IPlatformIconLoader>().ToConstant(new PlatformIconLoaderStub())
                 .Bind<PlatformHotkeyConfiguration>().ToSingleton<PlatformHotkeyConfiguration>()
-                .Bind<IRenderLoop>().ToSingleton<RenderLoop>()
                 .Bind<IRenderTimer>().ToConstant(Timer)
                 .Bind<IDispatcherImpl>().ToConstant(DispatcherImpl.Instance)
                 .Bind<IKeyboardDevice>().ToConstant(keyboard);
 
-                Compositor = new Compositor(
-                    AvaloniaLocator.Current.GetRequiredService<IRenderLoop>(),
-                    AvaloniaLocator.Current.GetService<IPlatformGraphics>());
+                Compositor = new Compositor(AvaloniaLocator.Current.GetService<IPlatformGraphics>());
         }
-
-
     }
 }
 
diff --git a/tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Coercion.cs b/tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Coercion.cs
index 0d0456dbda..42720cbb4c 100644
--- a/tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Coercion.cs
+++ b/tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Coercion.cs
@@ -124,6 +124,19 @@ namespace Avalonia.Base.UnitTests
             Assert.Equal(2, target.CoreChanges.Count);
         }
 
+        [Fact]
+        public void CoerceValue_Calls_Coerce_Callback_Only_Once()
+        {
+            var target = new Class1 { Foo = 99 };
+
+            target.MaxFoo = 50;
+            
+            target.CoerceFooInvocations.Clear();
+            target.CoerceValue(Class1.FooProperty);
+
+            Assert.Equal(new[] { 99 }, target.CoerceFooInvocations);
+        }
+
         [Fact]
         public void Coerced_Value_Can_Be_Restored_If_Limit_Changed()
         {
@@ -218,6 +231,18 @@ namespace Avalonia.Base.UnitTests
             Assert.Equal(1, raised);
         }
 
+        [Fact]
+        public void Default_Value_Is_Coerced_Only_Once()
+        {
+            var target = new Class1();
+
+            target.MinFoo = 20;
+            target.CoerceFooInvocations.Clear();
+            target.CoerceValue(Class1.FooProperty);
+
+            Assert.Equal(new[] { 11 }, target.CoerceFooInvocations);
+        }
+
         [Fact]
         public void ClearValue_Respects_Coerced_Default_Value()
         {
@@ -338,10 +363,12 @@ namespace Avalonia.Base.UnitTests
             public int MinFoo { get; set; } = 0;
             public int MaxFoo { get; set; } = 100;
 
+            public List<int> CoerceFooInvocations { get; } = new();
             public List<AvaloniaPropertyChangedEventArgs> CoreChanges { get; } = new();
 
             public static int CoerceFoo(AvaloniaObject instance, int value)
             {
+                (instance as Class1)?.CoerceFooInvocations.Add(value);
                 return instance is Class1 o ? 
                     Math.Clamp(value, o.MinFoo, o.MaxFoo) :
                     Math.Clamp(value, 0, 100);
diff --git a/tests/Avalonia.Base.UnitTests/Composition/BatchStreamTests.cs b/tests/Avalonia.Base.UnitTests/Composition/BatchStreamTests.cs
index a1b55257e6..5118ac7f71 100644
--- a/tests/Avalonia.Base.UnitTests/Composition/BatchStreamTests.cs
+++ b/tests/Avalonia.Base.UnitTests/Composition/BatchStreamTests.cs
@@ -12,8 +12,8 @@ public class BatchStreamTests
     public void BatchStreamCorrectlyWritesAndReadsData()
     {
         var data = new BatchStreamData();
-        var memPool = new BatchStreamMemoryPool(100, _ => { });
-        var objPool = new BatchStreamObjectPool<object>(10, _ => { });
+        var memPool = new BatchStreamMemoryPool(false, 100, _ => { });
+        var objPool = new BatchStreamObjectPool<object>(false, 10, _ => { });
 
         var guids = new List<Guid>();
         var objects = new List<object>();
diff --git a/tests/Avalonia.Base.UnitTests/Composition/CompositionAnimationTests.cs b/tests/Avalonia.Base.UnitTests/Composition/CompositionAnimationTests.cs
index 510d7c2c6d..b1ca75d018 100644
--- a/tests/Avalonia.Base.UnitTests/Composition/CompositionAnimationTests.cs
+++ b/tests/Avalonia.Base.UnitTests/Composition/CompositionAnimationTests.cs
@@ -78,8 +78,9 @@ public class CompositionAnimationTests
     [Theory]
     public void GenericCheck(AnimationData data)
     {
+        using var scope = AvaloniaLocator.EnterScope();
         var compositor =
-            new Compositor(new RenderLoop(new CompositorTestServices.ManualRenderTimer(), new DummyDispatcher()), null);
+            new Compositor(new RenderLoop(new CompositorTestServices.ManualRenderTimer()), null);
         var target = compositor.CreateSolidColorVisual();
         var ani = new ScalarKeyFrameAnimation(null);
         foreach (var frame in data.Frames)
diff --git a/tests/Avalonia.Base.UnitTests/Input/MouseDeviceTests.cs b/tests/Avalonia.Base.UnitTests/Input/MouseDeviceTests.cs
index 642e762c1b..8aabd22b08 100644
--- a/tests/Avalonia.Base.UnitTests/Input/MouseDeviceTests.cs
+++ b/tests/Avalonia.Base.UnitTests/Input/MouseDeviceTests.cs
@@ -3,6 +3,7 @@ using Avalonia.Input;
 using Avalonia.Input.Raw;
 using Avalonia.Media;
 using Avalonia.Platform;
+using Avalonia.Rendering;
 using Avalonia.Threading;
 using Avalonia.UnitTests;
 using Moq;
@@ -29,12 +30,12 @@ namespace Avalonia.Base.UnitTests.Input
                     inputManager: new InputManager(),
                     dispatcherImpl: dispatcherMock.Object));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var device = new MouseDevice();
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
 
             var control = new Control();
-            var root = CreateInputRoot(impl.Object, control);
+            var root = CreateInputRoot(impl.Object, control, renderer.Object);
            
             MouseButton button = default;
 
@@ -64,9 +65,9 @@ namespace Avalonia.Base.UnitTests.Input
         {
             using var app = UnitTestApplication.Start(new TestServices(inputManager: new InputManager()));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var device = new MouseDevice();
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
 
             Canvas control;
             Panel rootChild;
@@ -76,7 +77,7 @@ namespace Avalonia.Base.UnitTests.Input
                 {
                     (control = new Canvas())
                 }
-            });
+            }, renderer.Object);
 
             // Synthesize event to receive a pointer.
             IPointer result = null;
@@ -102,9 +103,9 @@ namespace Avalonia.Base.UnitTests.Input
         {
             using var app = UnitTestApplication.Start(new TestServices(inputManager: new InputManager()));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var device = new MouseDevice();
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
 
             Border border;
             var root = CreateInputRoot(impl.Object, new Panel
@@ -117,7 +118,7 @@ namespace Avalonia.Base.UnitTests.Input
                         RenderTransform = new TranslateTransform(10, 0),
                     })
                 }
-            });
+            }, renderer.Object);
            
            
             Point? result = null;
diff --git a/tests/Avalonia.Base.UnitTests/Input/PointerOverTests.cs b/tests/Avalonia.Base.UnitTests/Input/PointerOverTests.cs
index ae6b601896..62c99a553b 100644
--- a/tests/Avalonia.Base.UnitTests/Input/PointerOverTests.cs
+++ b/tests/Avalonia.Base.UnitTests/Input/PointerOverTests.cs
@@ -24,9 +24,9 @@ namespace Avalonia.Base.UnitTests.Input
                 inputManager: new InputManager(),
                 focusManager: new FocusManager()));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var device = CreatePointerDeviceMock().Object;
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
 
             Canvas canvas;
             var root = CreateInputRoot(impl.Object, new Panel
@@ -35,7 +35,7 @@ namespace Avalonia.Base.UnitTests.Input
                 {
                     (canvas = new Canvas())
                 }
-            });
+            }, renderer.Object);
 
             SetHit(renderer, canvas);
             impl.Object.Input!(CreateRawPointerMovedArgs(device, root));
@@ -52,9 +52,9 @@ namespace Avalonia.Base.UnitTests.Input
         {
             using var app = UnitTestApplication.Start(new TestServices(inputManager: new InputManager()));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var device = CreatePointerDeviceMock().Object;
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
 
             Canvas canvas;
             Border border;
@@ -70,7 +70,7 @@ namespace Avalonia.Base.UnitTests.Input
                         Child = decorator = new Decorator(),
                     })
                 }
-            });
+            }, renderer.Object);
 
             SetHit(renderer, decorator);
             impl.Object.Input!(CreateRawPointerMovedArgs(device, root));
@@ -95,9 +95,9 @@ namespace Avalonia.Base.UnitTests.Input
         {
             using var app = UnitTestApplication.Start(new TestServices(inputManager: new InputManager()));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var device = CreatePointerDeviceMock(pointerType: PointerType.Touch).Object;
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
 
             Canvas canvas;
 
@@ -107,7 +107,7 @@ namespace Avalonia.Base.UnitTests.Input
                 {
                     (canvas = new Canvas())
                 }
-            });
+            }, renderer.Object);
 
             SetHit(renderer, canvas);
             impl.Object.Input!(CreateRawPointerMovedArgs(device, root));
@@ -121,10 +121,10 @@ namespace Avalonia.Base.UnitTests.Input
         {
             using var app = UnitTestApplication.Start(new TestServices(inputManager: new InputManager()));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var pointer = new Mock<IPointer>();
             var device = CreatePointerDeviceMock(pointer.Object).Object;
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
 
             Canvas canvas;
             Border border;
@@ -140,7 +140,7 @@ namespace Avalonia.Base.UnitTests.Input
                         Child = decorator = new Decorator(),
                     })
                 }
-            });
+            }, renderer.Object);
 
             SetHit(renderer, canvas);
             pointer.SetupGet(p => p.Captured).Returns(decorator);
@@ -157,9 +157,9 @@ namespace Avalonia.Base.UnitTests.Input
         {
             using var app = UnitTestApplication.Start(new TestServices(inputManager: new InputManager()));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var device = CreatePointerDeviceMock().Object;
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
 
             Canvas canvas;
             Border border;
@@ -175,7 +175,7 @@ namespace Avalonia.Base.UnitTests.Input
                         Child = decorator = new Decorator(),
                     })
                 }
-            });
+            }, renderer.Object);
 
             SetHit(renderer, canvas);
             impl.Object.Input!(CreateRawPointerMovedArgs(device, root));
@@ -203,9 +203,9 @@ namespace Avalonia.Base.UnitTests.Input
         {
             using var app = UnitTestApplication.Start(new TestServices(inputManager: new InputManager()));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var deviceMock = CreatePointerDeviceMock();
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
             var result = new List<(object?, string)>();
 
             void HandleEvent(object? sender, PointerEventArgs e)
@@ -227,7 +227,7 @@ namespace Avalonia.Base.UnitTests.Input
                         Child = decorator = new Decorator(),
                     })
                 }
-            });
+            }, renderer.Object);
 
             AddEnteredExitedHandlers(HandleEvent, canvas, decorator);
 
@@ -258,9 +258,9 @@ namespace Avalonia.Base.UnitTests.Input
         {
             using var app = UnitTestApplication.Start(new TestServices(inputManager: new InputManager()));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var deviceMock = CreatePointerDeviceMock();
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
             var result = new List<(object?, string)>();
 
             void HandleEvent(object? sender, PointerEventArgs e)
@@ -282,7 +282,7 @@ namespace Avalonia.Base.UnitTests.Input
                         Child = decorator = new Decorator(),
                     })
                 }
-            });
+            }, renderer.Object);
 
             SetHit(renderer, canvas);
             impl.Object.Input!(CreateRawPointerMovedArgs(deviceMock.Object, root));
@@ -309,9 +309,9 @@ namespace Avalonia.Base.UnitTests.Input
             using var app = UnitTestApplication.Start(new TestServices(inputManager: new InputManager()));
 
             var expectedPosition = new Point(15, 15);
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var deviceMock = CreatePointerDeviceMock();
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
             var result = new List<(object?, string, Point)>();
 
             void HandleEvent(object? sender, PointerEventArgs e)
@@ -327,7 +327,7 @@ namespace Avalonia.Base.UnitTests.Input
                 {
                     (canvas = new Canvas())
                 }
-            });
+            }, renderer.Object);
 
             AddEnteredExitedHandlers(HandleEvent, root, canvas);
 
@@ -348,14 +348,17 @@ namespace Avalonia.Base.UnitTests.Input
                 result);
         }
 
+        void RaiseSceneInvalidated(TopLevel tl) =>
+            tl.Renderer.TriggerSceneInvalidatedForUnitTests(new Rect(0, 0, 10000, 10000));
+
         [Fact]
         public void Render_Invalidation_Should_Affect_PointerOver()
         {
             using var app = UnitTestApplication.Start(new TestServices(inputManager: new InputManager()));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var deviceMock = CreatePointerDeviceMock();
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
 
             var invalidateRect = new Rect(0, 0, 15, 15);
             var lastClientPosition = new Point(1, 5);
@@ -374,7 +377,7 @@ namespace Avalonia.Base.UnitTests.Input
                 {
                     (canvas = new Canvas())
                 }
-            });
+            }, renderer.Object);
             AddEnteredExitedHandlers(HandleEvent, root, canvas);
 
             // Let input know about latest device.
@@ -383,12 +386,12 @@ namespace Avalonia.Base.UnitTests.Input
             Assert.True(canvas.IsPointerOver);
 
             SetHit(renderer, canvas);
-            renderer.Raise(r => r.SceneInvalidated += null, new SceneInvalidatedEventArgs((IRenderRoot)root, invalidateRect));
+            RaiseSceneInvalidated(root);
             Assert.True(canvas.IsPointerOver);
 
             // Raise SceneInvalidated again, but now hide element from the hittest.
             SetHit(renderer, null);
-            renderer.Raise(r => r.SceneInvalidated += null, new SceneInvalidatedEventArgs((IRenderRoot)root, invalidateRect));
+            RaiseSceneInvalidated(root);
             Assert.False(canvas.IsPointerOver);
 
             Assert.Equal(
@@ -407,9 +410,9 @@ namespace Avalonia.Base.UnitTests.Input
         {
             using var app = UnitTestApplication.Start(new TestServices(inputManager: new InputManager()));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var deviceMock = CreatePointerDeviceMock();
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
 
             var invalidateRect = new Rect(0, 0, 15, 15);
 
@@ -422,7 +425,7 @@ namespace Avalonia.Base.UnitTests.Input
                     (canvas1 = new Canvas()),
                     (canvas2 = new Canvas())
                 }
-            });
+            }, renderer.Object);
 
             canvas1.PointerMoved += (s, a) => a.Pointer.Capture(canvas1);
 
@@ -433,7 +436,7 @@ namespace Avalonia.Base.UnitTests.Input
             Assert.False(canvas2.IsPointerOver);
 
             SetHit(renderer, canvas2);
-            renderer.Raise(r => r.SceneInvalidated += null, new SceneInvalidatedEventArgs((IRenderRoot)root, invalidateRect));
+            RaiseSceneInvalidated(root);
             Assert.False(canvas1.IsPointerOver);
             Assert.True(canvas2.IsPointerOver);
         }
@@ -444,9 +447,9 @@ namespace Avalonia.Base.UnitTests.Input
         {
             using var app = UnitTestApplication.Start(new TestServices(inputManager: new InputManager()));
 
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var deviceMock = CreatePointerDeviceMock();
-            var impl = CreateTopLevelImplMock(renderer.Object);
+            var impl = CreateTopLevelImplMock();
 
             var lastClientPosition = new Point(1, 5);
             var invalidateRect = new Rect(0, 0, 15, 15);
@@ -465,7 +468,7 @@ namespace Avalonia.Base.UnitTests.Input
                 {
                     (canvas = new Canvas())
                 }
-            });
+            }, renderer.Object);
 
             AddEnteredExitedHandlers(HandleEvent, root, canvas);
 
diff --git a/tests/Avalonia.Base.UnitTests/Input/PointerTestsBase.cs b/tests/Avalonia.Base.UnitTests/Input/PointerTestsBase.cs
index 5915343764..b4d20f2496 100644
--- a/tests/Avalonia.Base.UnitTests/Input/PointerTestsBase.cs
+++ b/tests/Avalonia.Base.UnitTests/Input/PointerTestsBase.cs
@@ -7,6 +7,8 @@ using Avalonia.Input;
 using Avalonia.Input.Raw;
 using Avalonia.Platform;
 using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
+using Avalonia.UnitTests;
 using Avalonia.VisualTree;
 using Moq;
 
@@ -14,7 +16,7 @@ namespace Avalonia.Base.UnitTests.Input;
 
 public abstract class PointerTestsBase
 {
-    protected static void SetHit(Mock<IRenderer> renderer, Control? hit)
+    private protected static void SetHit(Mock<IHitTester> renderer, Control? hit)
     {
         renderer.Setup(x => x.HitTest(It.IsAny<Point>(), It.IsAny<Visual>(), It.IsAny<Func<Visual, bool>>()))
             .Returns(hit is null ? Array.Empty<Control>() : new[] { hit });
@@ -29,27 +31,28 @@ public abstract class PointerTestsBase
             .Callback(() => element.RaiseEvent(CreatePointerMovedArgs(root, element)));
     }
 
-    protected static Mock<IWindowImpl> CreateTopLevelImplMock(IRenderer renderer)
+    private protected static Mock<IWindowImpl> CreateTopLevelImplMock()
     {
         var impl = new Mock<IWindowImpl>();
         impl.DefaultValue = DefaultValue.Mock;
         impl.SetupAllProperties();
         impl.SetupGet(r => r.RenderScaling).Returns(1);
         impl.Setup(r => r.TryGetFeature(It.IsAny<Type>())).Returns(null);
-        impl.Setup(r => r.CreateRenderer(It.IsAny<IRenderRoot>())).Returns(renderer);
+        impl.Setup(r => r.Compositor).Returns(RendererMocks.CreateDummyCompositor());
         impl.Setup(r => r.PointToScreen(It.IsAny<Point>())).Returns<Point>(p => new PixelPoint((int)p.X, (int)p.Y));
         impl.Setup(r => r.PointToClient(It.IsAny<PixelPoint>())).Returns<PixelPoint>(p => new Point(p.X, p.Y));
         return impl;
     }
 
-    protected static IInputRoot CreateInputRoot(IWindowImpl impl, Control child)
+    private protected static TopLevel CreateInputRoot(IWindowImpl impl, Control child, IHitTester hitTester)
     {
         var root = new Window(impl)
         {
             Width = 100,
             Height = 100,
             Content = child,
-            Template = new FuncControlTemplate<Window>((w, _) => new ContentPresenter { Content = w.Content })
+            Template = new FuncControlTemplate<Window>((w, _) => new ContentPresenter { Content = w.Content }),
+            HitTesterOverride = hitTester
         };
         root.Show();
         return root;
diff --git a/tests/Avalonia.Base.UnitTests/Layout/LayoutManagerTests.cs b/tests/Avalonia.Base.UnitTests/Layout/LayoutManagerTests.cs
index cadf23c754..dacd468a67 100644
--- a/tests/Avalonia.Base.UnitTests/Layout/LayoutManagerTests.cs
+++ b/tests/Avalonia.Base.UnitTests/Layout/LayoutManagerTests.cs
@@ -3,11 +3,12 @@ using System.Linq;
 using Avalonia.Controls;
 using Avalonia.Layout;
 using Avalonia.Threading;
+using Avalonia.UnitTests;
 using Xunit;
 
 namespace Avalonia.Base.UnitTests.Layout
 {
-    public class LayoutManagerTests
+    public class LayoutManagerTests : ScopedTestBase
     {
         [Fact]
         public void Measures_And_Arranges_InvalidateMeasured_Control()
@@ -476,7 +477,7 @@ namespace Avalonia.Base.UnitTests.Layout
             root.LayoutManager.InvalidateArrange(control);
             root.LayoutManager.ExecuteInitialLayoutPass();
             
-            Dispatcher.UIThread.RunJobs(DispatcherPriority.Layout);
+            Dispatcher.UIThread.RunJobs(DispatcherPriority.Render);
             
             Assert.Equal(1, layoutCount);
         }
diff --git a/tests/Avalonia.Base.UnitTests/Layout/LayoutableTests_EffectiveViewportChanged.cs b/tests/Avalonia.Base.UnitTests/Layout/LayoutableTests_EffectiveViewportChanged.cs
index 536c766a7d..5a493cb741 100644
--- a/tests/Avalonia.Base.UnitTests/Layout/LayoutableTests_EffectiveViewportChanged.cs
+++ b/tests/Avalonia.Base.UnitTests/Layout/LayoutableTests_EffectiveViewportChanged.cs
@@ -182,6 +182,7 @@ namespace Avalonia.Base.UnitTests.Layout
         [Fact]
         public async Task Scrolled_ScrollViewer_Determines_EffectiveViewport()
         {
+            using var scope = AvaloniaLocator.EnterScope();
             await RunOnUIThread.Execute(async () =>
             {
                 var root = CreateRoot();
@@ -207,6 +208,7 @@ namespace Avalonia.Base.UnitTests.Layout
         [Fact]
         public async Task Moving_Parent_Updates_EffectiveViewport()
         {
+            using var scope = AvaloniaLocator.EnterScope();
             await RunOnUIThread.Execute(async () =>
             {
                 var root = CreateRoot();
@@ -234,6 +236,7 @@ namespace Avalonia.Base.UnitTests.Layout
         [Fact]
         public async Task Translate_Transform_Doesnt_Affect_EffectiveViewport()
         {
+            using var scope = AvaloniaLocator.EnterScope();
             await RunOnUIThread.Execute(async () =>
             {
                 var root = CreateRoot();
@@ -256,6 +259,7 @@ namespace Avalonia.Base.UnitTests.Layout
         [Fact]
         public async Task Translate_Transform_On_Parent_Affects_EffectiveViewport()
         {
+            using var scope = AvaloniaLocator.EnterScope();
             await RunOnUIThread.Execute(async () =>
             {
                 var root = CreateRoot();
@@ -286,6 +290,7 @@ namespace Avalonia.Base.UnitTests.Layout
         [Fact]
         public async Task Rotate_Transform_On_Parent_Affects_EffectiveViewport()
         {
+            using var scope = AvaloniaLocator.EnterScope();
             await RunOnUIThread.Execute(async () =>
             {
                 var root = CreateRoot();
diff --git a/tests/Avalonia.Base.UnitTests/Rendering/CompositorTestsBase.cs b/tests/Avalonia.Base.UnitTests/Rendering/CompositorTestsBase.cs
index fed193e973..2cb181778b 100644
--- a/tests/Avalonia.Base.UnitTests/Rendering/CompositorTestsBase.cs
+++ b/tests/Avalonia.Base.UnitTests/Rendering/CompositorTestsBase.cs
@@ -22,7 +22,7 @@ using Xunit;
 
 namespace Avalonia.Base.UnitTests.Rendering;
 
-public class CompositorTestsBase
+public class CompositorTestsBase : ScopedTestBase
 {
     protected class CompositorCanvas : CompositorTestServices
     {
diff --git a/tests/Avalonia.Base.UnitTests/Rendering/RenderLoopTests.cs b/tests/Avalonia.Base.UnitTests/Rendering/RenderLoopTests.cs
deleted file mode 100644
index 97740fab00..0000000000
--- a/tests/Avalonia.Base.UnitTests/Rendering/RenderLoopTests.cs
+++ /dev/null
@@ -1,113 +0,0 @@
-using System;
-using System.Threading.Tasks;
-using Avalonia.Rendering;
-using Avalonia.Threading;
-using Moq;
-using Xunit;
-
-namespace Avalonia.Base.UnitTests.Rendering
-{
-    public class RenderLoopTests
-    {
-        [Fact]
-        public void RenderLoop_Update_Runs_On_Dispatcher()
-        {
-            var dispatcher = new Mock<IDispatcher>();
-
-            bool inDispatcher = false;
-
-            dispatcher.Setup(
-                d => d.Post(It.IsAny<Action>(), DispatcherPriority.Render))
-                .Callback((Action a, DispatcherPriority _) =>
-                {
-                    inDispatcher = true;
-                    a();
-                    inDispatcher = false;
-                });
-
-            var timer = new Mock<IRenderTimer>();
-
-            var loop = new RenderLoop(timer.Object, dispatcher.Object);
-
-            var renderTask = new Mock<IRenderLoopTask>();
-
-            renderTask.Setup(t => t.NeedsUpdate).Returns(true);
-            renderTask.Setup(t => t.Update(It.IsAny<TimeSpan>()))
-                .Callback((TimeSpan _) => Assert.True(inDispatcher));
-
-            loop.Add(renderTask.Object);
-
-            timer.Raise(t => t.Tick += null, TimeSpan.Zero);
-
-            renderTask.Verify(t => t.Update(It.IsAny<TimeSpan>()), Times.Once());
-        }
-
-        [Fact]
-        public void RenderLoop_Does_Not_Update_When_No_Tasks_Need_Update()
-        {
-            var dispatcher = new Mock<IDispatcher>();
-            dispatcher.Setup(
-                    d => d.Post(It.IsAny<Action>(), DispatcherPriority.Render))
-                .Callback((Action a, DispatcherPriority _) => a());
-
-            var timer = new Mock<IRenderTimer>();
-            var loop = new RenderLoop(timer.Object, dispatcher.Object);
-            var renderTask = new Mock<IRenderLoopTask>();
-            renderTask.Setup(t => t.NeedsUpdate).Returns(false);
-
-            loop.Add(renderTask.Object);
-            timer.Raise(t => t.Tick += null, TimeSpan.Zero);
-            
-            renderTask.Verify(t => t.Update(It.IsAny<TimeSpan>()), Times.Never());
-        }
-
-        [Fact]
-        public void RenderLoop_Render_Runs_Off_Dispatcher()
-        {
-            var dispatcher = new Mock<IDispatcher>();
-            bool inDispatcher = false;
-            dispatcher.Setup(
-                d => d.Post(It.IsAny<Action>(), DispatcherPriority.Render))
-                .Callback((Action a, DispatcherPriority _) =>
-                {
-                    inDispatcher = true;
-                    a();
-                    inDispatcher = false;
-                });
-
-            var timer = new Mock<IRenderTimer>();
-            var loop = new RenderLoop(timer.Object, dispatcher.Object);
-
-            var renderTask = new Mock<IRenderLoopTask>();
-
-            renderTask.Setup(t => t.NeedsUpdate).Returns(true);
-            renderTask.Setup(t => t.Render())
-                .Callback(() => Assert.False(inDispatcher));
-
-            loop.Add(renderTask.Object);
-            timer.Raise(t => t.Tick += null, TimeSpan.Zero);
-
-            renderTask.Verify(t => t.Update(It.IsAny<TimeSpan>()), Times.Once());
-        }
-        
-        [Fact]
-        public void RenderLoop_Passes_Tick_Count_To_Update()
-        {
-            var dispatcher = new Mock<IDispatcher>();
-            dispatcher.Setup(
-                d => d.Post(It.IsAny<Action>(), DispatcherPriority.Render))
-                .Callback((Action a, DispatcherPriority _) => a());
-
-            var timer = new Mock<IRenderTimer>();
-            var loop = new RenderLoop(timer.Object, dispatcher.Object);
-            var renderTask = new Mock<IRenderLoopTask>();
-            renderTask.Setup(t => t.NeedsUpdate).Returns(true);
-
-            loop.Add(renderTask.Object);
-            var time = new TimeSpan(123456789L);
-            timer.Raise(t => t.Tick += null, time);
-
-            renderTask.Verify(t => t.Update(time), Times.Once());
-        }
-    }
-}
diff --git a/tests/Avalonia.Base.UnitTests/Rendering/SceneGraph/DrawOperationTests.cs b/tests/Avalonia.Base.UnitTests/Rendering/SceneGraph/DrawOperationTests.cs
index 1a5ce0ef94..d0eb34b509 100644
--- a/tests/Avalonia.Base.UnitTests/Rendering/SceneGraph/DrawOperationTests.cs
+++ b/tests/Avalonia.Base.UnitTests/Rendering/SceneGraph/DrawOperationTests.cs
@@ -14,7 +14,7 @@ using Xunit;
 
 namespace Avalonia.Base.UnitTests.Rendering.SceneGraph
 {  
-    public class DrawOperationTests
+    public class DrawOperationTests : ScopedTestBase
     {
 
         class TestContext
@@ -22,11 +22,9 @@ namespace Avalonia.Base.UnitTests.Rendering.SceneGraph
             private readonly Compositor _compositor;
             public RenderDataDrawingContext Context { get; }
 
-            public TestContext()
+            public TestContext(CompositorTestServices services)
             {
-                _compositor = new Compositor(new RenderLoop(
-                    new CompositorTestServices.ManualRenderTimer(),
-                    new Dispatcher(new NullDispatcherImpl())), null);
+                _compositor = services.Compositor;
                 Context = new RenderDataDrawingContext(_compositor);
             }
 
@@ -46,10 +44,17 @@ namespace Avalonia.Base.UnitTests.Rendering.SceneGraph
             }
         }
 
+        private CompositorTestServices _services = new();
+        public override void Dispose()
+        {
+            _services.Dispose();
+            base.Dispose();
+        }
+
         [Fact]
         public void Empty_Bounds_Remain_Empty()
         {
-            var ctx = new TestContext();
+            var ctx = new TestContext(_services);
             ctx.Context.DrawRectangle(Brushes.Black, null, default);
             
             Assert.Null(ctx.GetBounds());
@@ -72,7 +77,7 @@ namespace Avalonia.Base.UnitTests.Rendering.SceneGraph
             double expectedWidth,
             double expectedHeight)
         {
-            var ctx = new TestContext();
+            var ctx = new TestContext(_services);
             using (ctx.Context.PushTransform(Matrix.CreateScale(scaleX, scaleY)))
                 ctx.Context.DrawRectangle(null, new ImmutablePen(Brushes.Black, penThickness), new Rect(x, y, width, height));
 
@@ -84,7 +89,7 @@ namespace Avalonia.Base.UnitTests.Rendering.SceneGraph
         {
             var bitmap = RefCountable.Create(Mock.Of<IBitmapImpl>());
 
-            var ctx = new TestContext();
+            var ctx = new TestContext(_services);
             ctx.Context.DrawBitmap(bitmap, 1, new Rect(1, 1, 1, 1), new Rect(1, 1, 1, 1));
             var renderData = ctx.Context.GetRenderResults()!;
             Assert.Equal(2, bitmap.RefCount);
@@ -112,7 +117,7 @@ namespace Avalonia.Base.UnitTests.Rendering.SceneGraph
         [Fact]
         public void HitTest_On_Geometry_Node_With_Zero_Transform_Does_Not_Throw()
         {
-            var ctx = new TestContext();
+            var ctx = new TestContext(_services);
             using (ctx.Context.PushTransform(new Matrix()))
                 ctx.Context.DrawGeometry(Brushes.Black, null, Mock.Of<IGeometryImpl>());
             Assert.False(ctx.Context.GetRenderResults()!.HitTest(default));
@@ -121,11 +126,24 @@ namespace Avalonia.Base.UnitTests.Rendering.SceneGraph
         [Fact]
         public void HitTest_RectangleNode_With_Transform_Hits()
         {
-            var ctx = new TestContext();
+            var ctx = new TestContext(_services);
             using (ctx.Context.PushTransform(Matrix.CreateTranslation(20, 20)))
                 ctx.Context.DrawRectangle(Brushes.Black, null, new RoundedRect(new Rect(0, 0, 10, 10)));
 
             Assert.True(ctx.Context.GetRenderResults()!.HitTest(new Point(25, 25)));
         }
+        
+        [Fact]
+        public void Empty_Push_Pop_Sequence_Produces_No_Results()
+        {
+            var ctx = new TestContext(_services);
+            using (ctx.Context.PushTransform(Matrix.CreateTranslation(20, 20)))
+            using (ctx.Context.PushOpacity(1))
+            {
+
+            }
+
+            Assert.Null(ctx.Context.GetRenderResults());
+        }
     }
 }
diff --git a/tests/Avalonia.Base.UnitTests/Styling/StyleTests.cs b/tests/Avalonia.Base.UnitTests/Styling/StyleTests.cs
index 4f5d1b8ec8..ca6d1e5326 100644
--- a/tests/Avalonia.Base.UnitTests/Styling/StyleTests.cs
+++ b/tests/Avalonia.Base.UnitTests/Styling/StyleTests.cs
@@ -13,7 +13,7 @@ using Xunit;
 
 namespace Avalonia.Base.UnitTests.Styling
 {
-    public class StyleTests
+    public class StyleTests : ScopedTestBase
     {
         [Fact]
         public void Style_With_Only_Type_Selector_Should_Update_Value()
diff --git a/tests/Avalonia.Base.UnitTests/Styling/StyledElementTests.cs b/tests/Avalonia.Base.UnitTests/Styling/StyledElementTests.cs
index 20931bfebc..197dde5cc0 100644
--- a/tests/Avalonia.Base.UnitTests/Styling/StyledElementTests.cs
+++ b/tests/Avalonia.Base.UnitTests/Styling/StyledElementTests.cs
@@ -330,7 +330,7 @@ namespace Avalonia.Base.UnitTests.Styling
         [Fact]
         public void Style_Is_Removed_When_Control_Removed_From_Logical_Tree()
         {
-            var app = UnitTestApplication.Start();
+            using var app = UnitTestApplication.Start();
             var target = new Border();
             var root = new TestRoot
             {
@@ -579,7 +579,7 @@ namespace Avalonia.Base.UnitTests.Styling
         public void SetParent_Does_Not_Crash_Due_To_Reentrancy()
         {
             // Issue #3708
-            var app = UnitTestApplication.Start(TestServices.StyledWindow);
+            using var app = UnitTestApplication.Start(TestServices.StyledWindow);
 
             ContentControl target;
             var root = new TestRoot
diff --git a/tests/Avalonia.Base.UnitTests/Styling/StyledElementTests_Theming.cs b/tests/Avalonia.Base.UnitTests/Styling/StyledElementTests_Theming.cs
index 6ba648af78..93711712d3 100644
--- a/tests/Avalonia.Base.UnitTests/Styling/StyledElementTests_Theming.cs
+++ b/tests/Avalonia.Base.UnitTests/Styling/StyledElementTests_Theming.cs
@@ -12,9 +12,9 @@ using Xunit;
 
 namespace Avalonia.Base.UnitTests.Styling;
 
-public class StyledElementTests_Theming
+public class StyledElementTests_Theming : ScopedTestBase
 {
-    public class InlineTheme
+    public class InlineTheme : ScopedTestBase
     {
         [Fact]
         public void Theme_Is_Applied_When_Attached_To_Logical_Tree()
@@ -342,7 +342,7 @@ public class StyledElementTests_Theming
         }
     }
 
-    public class ImplicitTheme
+    public class ImplicitTheme : ScopedTestBase
     {
         [Fact]
         public void Implicit_Theme_Is_Applied_When_Attached_To_Logical_Tree()
@@ -445,7 +445,7 @@ public class StyledElementTests_Theming
         }
     }
 
-    public class ThemeFromStyle
+    public class ThemeFromStyle : ScopedTestBase
     {
         [Fact]
         public void Theme_Is_Applied_When_Attached_To_Logical_Tree()
diff --git a/tests/Avalonia.Base.UnitTests/VisualTests.cs b/tests/Avalonia.Base.UnitTests/VisualTests.cs
index 11bdc4bc68..0150a06715 100644
--- a/tests/Avalonia.Base.UnitTests/VisualTests.cs
+++ b/tests/Avalonia.Base.UnitTests/VisualTests.cs
@@ -150,7 +150,7 @@ namespace Avalonia.Base.UnitTests
         [Fact]
         public void Attaching_To_Visual_Tree_Should_Invalidate_Visual()
         {
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IRenderer>();
             var child = new Decorator();
             var root = new TestRoot
             {
diff --git a/tests/Avalonia.Controls.UnitTests/ButtonTests.cs b/tests/Avalonia.Controls.UnitTests/ButtonTests.cs
index 2679d4ce06..1d62588ec0 100644
--- a/tests/Avalonia.Controls.UnitTests/ButtonTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/ButtonTests.cs
@@ -134,7 +134,7 @@ namespace Avalonia.Controls.UnitTests
         [Fact]
         public void Button_Raises_Click()
         {
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var pt = new Point(50, 50);
             renderer.Setup(r => r.HitTest(It.IsAny<Point>(), It.IsAny<Visual>(), It.IsAny<Func<Visual, bool>>()))
                 .Returns<Point, Visual, Func<Visual, bool>>((p, r, f) =>
@@ -165,7 +165,7 @@ namespace Avalonia.Controls.UnitTests
         [Fact]
         public void Button_Does_Not_Raise_Click_When_PointerReleased_Outside()
         {
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
 
             renderer.Setup(r => r.HitTest(It.IsAny<Point>(), It.IsAny<Visual>(), It.IsAny<Func<Visual, bool>>()))
                 .Returns<Point, Visual, Func<Visual, bool>>((p, r, f) =>
@@ -197,7 +197,7 @@ namespace Avalonia.Controls.UnitTests
         [Fact]
         public void Button_With_RenderTransform_Raises_Click()
         {
-            var renderer = RendererMocks.CreateRenderer();
+            var renderer = new Mock<IHitTester>();
             var pt = new Point(150, 50);
             renderer.Setup(r => r.HitTest(It.IsAny<Point>(), It.IsAny<Visual>(), It.IsAny<Func<Visual, bool>>()))
                 .Returns<Point, Visual, Func<Visual, bool>>((p, r, f) =>
@@ -383,10 +383,11 @@ namespace Avalonia.Controls.UnitTests
 
         private class TestButton : Button, IRenderRoot
         {
-            public TestButton(IRenderer renderer)
+            public TestButton(IHitTester hit)
             {
                 IsVisible = true;
-                Renderer = renderer;
+                HitTester = hit;
+                Renderer = new NullRenderer();
             }
 
             public new Rect Bounds
@@ -398,6 +399,7 @@ namespace Avalonia.Controls.UnitTests
             public Size ClientSize => throw new NotImplementedException();
 
             public IRenderer Renderer { get; }
+            public IHitTester HitTester { get; }
 
             public double RenderScaling => throw new NotImplementedException();
 
diff --git a/tests/Avalonia.Controls.UnitTests/ContentControlTests.cs b/tests/Avalonia.Controls.UnitTests/ContentControlTests.cs
index d5e4693666..02b6592097 100644
--- a/tests/Avalonia.Controls.UnitTests/ContentControlTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/ContentControlTests.cs
@@ -24,9 +24,9 @@ namespace Avalonia.Controls.UnitTests
             target.Content = "Foo";
             target.Template = GetTemplate();
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
-            var child = ((Visual)target).VisualChildren.Single();
+            var child = target.VisualChildren.Single();
             Assert.IsType<Border>(child);
             child = child.VisualChildren.Single();
             Assert.IsType<ContentPresenter>(child);
@@ -55,7 +55,7 @@ namespace Avalonia.Controls.UnitTests
             root.Child = target;
 
             target.ApplyTemplate();
-            ((Control)target.Presenter).ApplyTemplate();
+            target.Presenter.ApplyTemplate();
 
             foreach (Control child in target.GetTemplateChildren())
                 Assert.Equal("foo", child.Tag);
@@ -70,7 +70,7 @@ namespace Avalonia.Controls.UnitTests
             target.Template = GetTemplate();
             target.Content = child;
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             var contentPresenter = child.GetVisualParent<ContentPresenter>();
             Assert.Equal(target, contentPresenter.TemplatedParent);
@@ -85,7 +85,7 @@ namespace Avalonia.Controls.UnitTests
             target.Template = GetTemplate();
             target.Content = child;
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             Assert.Null(child.TemplatedParent);
         }
@@ -117,7 +117,7 @@ namespace Avalonia.Controls.UnitTests
             var child = new Control();
             target.Content = child;
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             Assert.Equal(child.Parent, target);
             Assert.Equal(child.GetLogicalParent(), target);
@@ -135,7 +135,7 @@ namespace Avalonia.Controls.UnitTests
 
             target.Content = "Foo";
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             var child = target.Presenter.Child;
 
@@ -152,7 +152,7 @@ namespace Avalonia.Controls.UnitTests
 
             target.Content = "Foo";
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             var child = target.Presenter.Child;
 
@@ -192,7 +192,7 @@ namespace Avalonia.Controls.UnitTests
             target.Template = GetTemplate();
             target.Content = child;
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             Assert.True(called);
         }
@@ -207,12 +207,12 @@ namespace Avalonia.Controls.UnitTests
             target.Template = GetTemplate();
             target.Content = child;
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             ((ILogical)target).LogicalChildren.CollectionChanged += (s, e) => called = true;
 
             target.Content = null;
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             Assert.True(called);
         }
@@ -228,12 +228,12 @@ namespace Avalonia.Controls.UnitTests
             target.Template = GetTemplate();
             target.Content = child1;
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             ((ILogical)target).LogicalChildren.CollectionChanged += (s, e) => called = true;
 
             target.Content = child2;
-            ((Control)target.Presenter).ApplyTemplate();
+            target.Presenter.ApplyTemplate();
 
             Assert.True(called);
         }
@@ -245,13 +245,13 @@ namespace Avalonia.Controls.UnitTests
 
             target.Template = GetTemplate();
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             target.Content = "Foo";
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
             Assert.Equal("Foo", ((TextBlock)target.Presenter.Child).Text);
             target.Content = "Bar";
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
             Assert.Equal("Bar", ((TextBlock)target.Presenter.Child).Text);
         }
 
@@ -263,7 +263,7 @@ namespace Avalonia.Controls.UnitTests
             target.Template = GetTemplate();
             target.Content = "Foo";
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             Assert.Equal("Foo", target.Presenter.Child.DataContext);
         }
@@ -276,7 +276,7 @@ namespace Avalonia.Controls.UnitTests
             target.Template = GetTemplate();
             target.Content = new TextBlock();
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             Assert.Null(target.Presenter.Child.DataContext);
         }
diff --git a/tests/Avalonia.Controls.UnitTests/ContextMenuTests.cs b/tests/Avalonia.Controls.UnitTests/ContextMenuTests.cs
index 803cc793fd..0c24a0d36e 100644
--- a/tests/Avalonia.Controls.UnitTests/ContextMenuTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/ContextMenuTests.cs
@@ -5,6 +5,7 @@ using Avalonia.Input;
 using Avalonia.Markup.Xaml;
 using Avalonia.Platform;
 using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
 using Avalonia.UnitTests;
 
 using Moq;
@@ -35,7 +36,7 @@ namespace Avalonia.Controls.UnitTests
 
                 int openedCount = 0;
 
-                sut.MenuOpened += (sender, args) =>
+                sut.Opened += (sender, args) =>
                 {
                     openedCount++;
                 };
@@ -138,7 +139,7 @@ namespace Avalonia.Controls.UnitTests
 
                 int openedCount = 0;
 
-                sut.MenuOpened += (sender, args) =>
+                sut.Opened += (sender, args) =>
                 {
                     openedCount++;
                 };
@@ -167,7 +168,7 @@ namespace Avalonia.Controls.UnitTests
 
                 bool opened = false;
 
-                sut.MenuOpened += (sender, args) =>
+                sut.Opened += (sender, args) =>
                 {
                     opened = true;
                 };
@@ -220,7 +221,7 @@ namespace Avalonia.Controls.UnitTests
 
                 int closedCount = 0;
 
-                sut.MenuClosed += (sender, args) =>
+                sut.Closed += (sender, args) =>
                 {
                     closedCount++;
                 };
@@ -258,7 +259,7 @@ namespace Avalonia.Controls.UnitTests
                 var tracker = 0;
 
                 var c = new ContextMenu();
-                c.ContextMenuClosing += (s, e) =>
+                c.Closing += (s, e) =>
                 {
                     tracker++;
                     e.Cancel = true;
@@ -430,7 +431,7 @@ namespace Avalonia.Controls.UnitTests
                 };
                 new Window { Content = target };
 
-                sut.ContextMenuOpening += (c, e) => { eventCalled = true; e.Cancel = true; };
+                sut.Opening += (c, e) => { eventCalled = true; e.Cancel = true; };
 
                 _mouse.Click(target, MouseButton.Right);
 
@@ -574,7 +575,7 @@ namespace Avalonia.Controls.UnitTests
                 var window = PreparedWindow(target);
                 var overlay = LightDismissOverlayLayer.GetLightDismissOverlayLayer(window);
 
-                sut.ContextMenuClosing += (c, e) => { eventCalled = true; e.Cancel = true; };
+                sut.Closing += (c, e) => { eventCalled = true; e.Cancel = true; };
 
                 window.Show();
 
@@ -595,10 +596,10 @@ namespace Avalonia.Controls.UnitTests
 
         private static Window PreparedWindow(object content = null)
         {
-            var renderer = RendererMocks.CreateRenderer();
+            
             var platform = AvaloniaLocator.Current.GetRequiredService<IWindowingPlatform>();
             var windowImpl = Mock.Get(platform.CreateWindow());
-            windowImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>())).Returns(renderer.Object);
+            windowImpl.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
 
             var w = new Window(windowImpl.Object) { Content = content };
             w.ApplyStyling();
diff --git a/tests/Avalonia.Controls.UnitTests/DesktopStyleApplicationLifetimeTests.cs b/tests/Avalonia.Controls.UnitTests/DesktopStyleApplicationLifetimeTests.cs
index 58811cd081..2ce32564ed 100644
--- a/tests/Avalonia.Controls.UnitTests/DesktopStyleApplicationLifetimeTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/DesktopStyleApplicationLifetimeTests.cs
@@ -5,6 +5,7 @@ using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Controls.Platform;
 using Avalonia.Platform;
 using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
 using Avalonia.Threading;
 using Avalonia.UnitTests;
 using Moq;
@@ -201,8 +202,7 @@ namespace Avalonia.Controls.UnitTests
         public void Impl_Closing_Should_Remove_Window_From_OpenWindows()
         {
             var windowImpl = new Mock<IWindowImpl>();
-            windowImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>()))
-                .Returns(() => RendererMocks.CreateRenderer().Object);
+            windowImpl.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
             windowImpl.SetupProperty(x => x.Closed);
             windowImpl.Setup(x => x.DesktopScaling).Returns(1);
             windowImpl.Setup(x => x.RenderScaling).Returns(1);
diff --git a/tests/Avalonia.Controls.UnitTests/FlyoutTests.cs b/tests/Avalonia.Controls.UnitTests/FlyoutTests.cs
index db12de9db9..e3f5983274 100644
--- a/tests/Avalonia.Controls.UnitTests/FlyoutTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/FlyoutTests.cs
@@ -8,6 +8,7 @@ using Avalonia.Markup.Xaml;
 using Avalonia.Media;
 using Avalonia.Platform;
 using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
 using Avalonia.UnitTests;
 using Avalonia.VisualTree;
 
@@ -569,10 +570,9 @@ namespace Avalonia.Controls.UnitTests
 
         private static Window PreparedWindow(object content = null)
         {
-            var renderer = RendererMocks.CreateRenderer();
             var platform = AvaloniaLocator.Current.GetRequiredService<IWindowingPlatform>();
             var windowImpl = Mock.Get(platform.CreateWindow());
-            windowImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>())).Returns(renderer.Object);
+            windowImpl.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
 
             var w = new Window(windowImpl.Object) { Content = content };
             w.ApplyTemplate();
diff --git a/tests/Avalonia.Controls.UnitTests/GridSplitterTests.cs b/tests/Avalonia.Controls.UnitTests/GridSplitterTests.cs
index 72ccead783..cdb8fb21fe 100644
--- a/tests/Avalonia.Controls.UnitTests/GridSplitterTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/GridSplitterTests.cs
@@ -7,7 +7,7 @@ using Xunit;
 
 namespace Avalonia.Controls.UnitTests
 {
-    public class GridSplitterTests
+    public class GridSplitterTests : ScopedTestBase
     {
         public GridSplitterTests()
         {
diff --git a/tests/Avalonia.Controls.UnitTests/GridTests.cs b/tests/Avalonia.Controls.UnitTests/GridTests.cs
index d372bb2af4..339a4a7cdd 100644
--- a/tests/Avalonia.Controls.UnitTests/GridTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/GridTests.cs
@@ -7,7 +7,7 @@ using Xunit.Abstractions;
 
 namespace Avalonia.Controls.UnitTests
 {
-    public class GridTests
+    public class GridTests : ScopedTestBase
     {
         private readonly ITestOutputHelper output;
 
diff --git a/tests/Avalonia.Controls.UnitTests/HeaderedItemsControlTests .cs b/tests/Avalonia.Controls.UnitTests/HeaderedItemsControlTests .cs
index 2cf4148fe3..78012a4d25 100644
--- a/tests/Avalonia.Controls.UnitTests/HeaderedItemsControlTests .cs	
+++ b/tests/Avalonia.Controls.UnitTests/HeaderedItemsControlTests .cs	
@@ -34,7 +34,7 @@ namespace Avalonia.Controls.UnitTests
 
             target.Header = "Foo";
             target.ApplyTemplate();
-            ((ContentPresenter)target.HeaderPresenter).UpdateChild();
+            target.HeaderPresenter.UpdateChild();
 
             var child = target.HeaderPresenter.Child;
 
diff --git a/tests/Avalonia.Controls.UnitTests/ListBoxTests.cs b/tests/Avalonia.Controls.UnitTests/ListBoxTests.cs
index 6d0b543ede..687338ece0 100644
--- a/tests/Avalonia.Controls.UnitTests/ListBoxTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/ListBoxTests.cs
@@ -20,7 +20,7 @@ using Xunit;
 
 namespace Avalonia.Controls.UnitTests
 {
-    public class ListBoxTests
+    public class ListBoxTests : ScopedTestBase
     {
         private MouseTestHelper _mouse = new MouseTestHelper();
 
diff --git a/tests/Avalonia.Controls.UnitTests/ListBoxTests_Single.cs b/tests/Avalonia.Controls.UnitTests/ListBoxTests_Single.cs
index ca7cc044ad..92ea2df2a9 100644
--- a/tests/Avalonia.Controls.UnitTests/ListBoxTests_Single.cs
+++ b/tests/Avalonia.Controls.UnitTests/ListBoxTests_Single.cs
@@ -305,7 +305,7 @@ namespace Avalonia.Controls.UnitTests
             scrollViewer.ApplyTemplate();
 
             // Then make the ScrollViewer create its child.
-            ((ContentPresenter)scrollViewer.Presenter).UpdateChild();
+            scrollViewer.Presenter.UpdateChild();
 
             // Now the ItemsPresenter should be reigstered, so apply its template.
             target.Presenter.ApplyTemplate();
diff --git a/tests/Avalonia.Controls.UnitTests/MaskedTextBoxTests.cs b/tests/Avalonia.Controls.UnitTests/MaskedTextBoxTests.cs
index dead810dbb..55450c3b4f 100644
--- a/tests/Avalonia.Controls.UnitTests/MaskedTextBoxTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/MaskedTextBoxTests.cs
@@ -14,6 +14,7 @@ using Avalonia.Layout;
 using Avalonia.Media;
 using Avalonia.Platform;
 using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
 using Avalonia.UnitTests;
 using Moq;
 using Xunit;
@@ -1010,8 +1011,7 @@ namespace Avalonia.Controls.UnitTests
         private static Mock<ITopLevelImpl> CreateMockTopLevelImpl()
         {
             var clipboard = new Mock<ITopLevelImpl>();
-            clipboard.Setup(r => r.CreateRenderer(It.IsAny<IRenderRoot>()))
-                .Returns(RendererMocks.CreateRenderer().Object);
+            clipboard.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
             clipboard.Setup(r => r.TryGetFeature(typeof(IClipboard)))
                 .Returns(new ClipboardStub());
             clipboard.SetupGet(x => x.RenderScaling).Returns(1);
diff --git a/tests/Avalonia.Controls.UnitTests/Presenters/ContentPresenterTests_InTemplate.cs b/tests/Avalonia.Controls.UnitTests/Presenters/ContentPresenterTests_InTemplate.cs
index 9042e84fa1..34a2776bcd 100644
--- a/tests/Avalonia.Controls.UnitTests/Presenters/ContentPresenterTests_InTemplate.cs
+++ b/tests/Avalonia.Controls.UnitTests/Presenters/ContentPresenterTests_InTemplate.cs
@@ -391,7 +391,7 @@ namespace Avalonia.Controls.UnitTests.Presenters
 
             templatedParent.ApplyTemplate();
 
-            return ((ContentPresenter)templatedParent.Presenter, templatedParent);
+            return (templatedParent.Presenter, templatedParent);
         }
 
         private class TestContentControl : ContentControl, IContentPresenterHost
diff --git a/tests/Avalonia.Controls.UnitTests/Primitives/PopupTests.cs b/tests/Avalonia.Controls.UnitTests/Primitives/PopupTests.cs
index 51399d1202..c1fd79fccc 100644
--- a/tests/Avalonia.Controls.UnitTests/Primitives/PopupTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/Primitives/PopupTests.cs
@@ -19,6 +19,7 @@ using Avalonia.Rendering;
 using System.Threading.Tasks;
 using Avalonia.Threading;
 using Avalonia.Interactivity;
+using Avalonia.Media;
 
 namespace Avalonia.Controls.UnitTests.Primitives
 {
@@ -564,12 +565,16 @@ namespace Avalonia.Controls.UnitTests.Primitives
         {
             using (CreateServices())
             {
-                var renderer = RendererMocks.CreateRenderer();
+                var compositor = RendererMocks.CreateDummyCompositor();
                 var platform = AvaloniaLocator.Current.GetRequiredService<IWindowingPlatform>();
                 var windowImpl = Mock.Get(platform.CreateWindow());
-                windowImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>())).Returns(renderer.Object);
+                windowImpl.Setup(x => x.Compositor).Returns(compositor);
+                var hitTester = new Mock<IHitTester>();
 
-                var window = new Window(windowImpl.Object);
+                var window = new Window(windowImpl.Object)
+                {
+                    HitTesterOverride = hitTester.Object
+                };
                 window.ApplyStyling();
                 window.ApplyTemplate();
 
@@ -584,7 +589,7 @@ namespace Avalonia.Controls.UnitTests.Primitives
                 var border = new Border();
                 window.Content = border;
 
-                renderer.Setup(x =>
+                hitTester.Setup(x =>
                     x.HitTestFirst(new Point(10, 15), window, It.IsAny<Func<Visual, bool>>()))
                     .Returns(border);
 
@@ -750,7 +755,7 @@ namespace Avalonia.Controls.UnitTests.Primitives
                 var window = PreparedWindow(popup);
                 window.Show();
                 popup.Open();
-                Dispatcher.UIThread.RunJobs(DispatcherPriority.Layout);
+                Dispatcher.UIThread.RunJobs(DispatcherPriority.AfterRender);
 
                 var raised = false;
                 if (popup.Host is PopupRoot popupRoot)
@@ -773,7 +778,7 @@ namespace Avalonia.Controls.UnitTests.Primitives
                     };
                 }
                 window.Position = new PixelPoint(10, 10);
-                Dispatcher.UIThread.RunJobs(DispatcherPriority.Layout);
+                Dispatcher.UIThread.RunJobs(DispatcherPriority.AfterRender);
                 Assert.False(raised);
             }
         }
@@ -803,7 +808,7 @@ namespace Avalonia.Controls.UnitTests.Primitives
                 var window = PreparedWindow(placementTarget);
                 window.Show();
                 popup.Open();
-                Dispatcher.UIThread.RunJobs(DispatcherPriority.Layout);
+                Dispatcher.UIThread.RunJobs(DispatcherPriority.AfterRender);
 
                 // The target's initial placement is (395,295) which is a 10x10 panel centered in a 800x600 window
                 Assert.Equal(placementTarget.Bounds, new Rect(395D, 295D, 10, 10));
@@ -834,7 +839,7 @@ namespace Avalonia.Controls.UnitTests.Primitives
                     };
                 }
                 window.PlatformImpl?.Resize(new Size(700D, 500D), WindowResizeReason.Unspecified);
-                Dispatcher.UIThread.RunJobs(DispatcherPriority.Layout);
+                Dispatcher.UIThread.RunJobs(DispatcherPriority.AfterRender);
                 Assert.True(raised);
             }
         }
@@ -864,7 +869,7 @@ namespace Avalonia.Controls.UnitTests.Primitives
                 var window = PreparedWindow(placementTarget);
                 window.Show();
                 popup.Open();
-                Dispatcher.UIThread.RunJobs(DispatcherPriority.Layout);
+                Dispatcher.UIThread.RunJobs(DispatcherPriority.AfterRender);
 
                 // The target's initial placement is (395,295) which is a 10x10 panel centered in a 800x600 window
                 Assert.Equal(placementTarget.Bounds, new Rect(395D, 295D, 10, 10));
@@ -890,7 +895,7 @@ namespace Avalonia.Controls.UnitTests.Primitives
                     };
                 }
                 window.PlatformImpl?.Resize(new Size(700D, 500D), WindowResizeReason.Unspecified);
-                Dispatcher.UIThread.RunJobs(DispatcherPriority.Layout);
+                Dispatcher.UIThread.RunJobs(DispatcherPriority.AfterRender);
                 Assert.False(raised);
             }
         }
@@ -919,7 +924,7 @@ namespace Avalonia.Controls.UnitTests.Primitives
                 var window = PreparedWindow(placementTarget);
                 window.Show();
                 popup.Open();
-                Dispatcher.UIThread.RunJobs(DispatcherPriority.Layout);
+                Dispatcher.UIThread.RunJobs();
 
                 // The target's initial placement is (395,295) which is a 10x10 panel centered in a 800x600 window
                 Assert.Equal(placementTarget.Bounds, new Rect(395D, 295D, 10, 10));
@@ -949,7 +954,7 @@ namespace Avalonia.Controls.UnitTests.Primitives
                     };
                 }
                 placementTarget.Margin = new Thickness(10, 0, 0, 0);
-                Dispatcher.UIThread.RunJobs(DispatcherPriority.Layout);
+                Dispatcher.UIThread.RunJobs();
                 Assert.True(raised);
             }
         }
@@ -979,7 +984,7 @@ namespace Avalonia.Controls.UnitTests.Primitives
                 var window = PreparedWindow(placementTarget);
                 window.Show();
                 popup.Open();
-                Dispatcher.UIThread.RunJobs(DispatcherPriority.Layout);
+                Dispatcher.UIThread.RunJobs();
 
                 // The target's initial placement is (395,295) which is a 10x10 panel centered in a 800x600 window
                 Assert.Equal(placementTarget.Bounds, new Rect(395D, 295D, 10, 10));
@@ -1005,7 +1010,7 @@ namespace Avalonia.Controls.UnitTests.Primitives
                     };
                 }
                 placementTarget.Margin = new Thickness(10, 0, 0, 0);
-                Dispatcher.UIThread.RunJobs(DispatcherPriority.Layout);
+                Dispatcher.UIThread.RunJobs();
                 Assert.False(raised);
             }
         }
@@ -1076,30 +1081,98 @@ namespace Avalonia.Controls.UnitTests.Primitives
             }
         }
 
-        private IDisposable CreateServices()
+        [Fact]
+        public void GetPosition_On_Control_In_Popup_Called_From_Parent_Should_Return_Valid_Coordinates()
         {
-            return UnitTestApplication.Start(TestServices.StyledWindow.With(windowingPlatform:
-                new MockWindowingPlatform(null,
-                    x =>
+            // This test only applies when using a PopupRoot host and not an overlay popup.
+            if (UsePopupHost)
+                return;
+
+            using (CreateServices())
+            {
+                var popupContent = new Border() { Height = 100, Width = 100, Background = Brushes.Red };
+                var popup = new Popup {  Child = popupContent, HorizontalOffset = 40, VerticalOffset = 40, Placement = PlacementMode.AnchorAndGravity,
+                    PlacementAnchor = PopupAnchor.TopLeft, PlacementGravity = PopupGravity.BottomRight};
+                var popupParent = new Border { Child = popup };
+                var root = PreparedWindow(popupParent);
+
+                popup.Open();
+
+                // Verify that the popup is positioned at 40,40 as descibed by the Horizontal/
+                // VerticalOffset: 10,10 becomes 50,50 in screen coordinates.
+                Assert.Equal(new PixelPoint(50, 50), popupContent.PointToScreen(new Point(10, 10)));
+
+                // The popup parent is positioned at 0,0 in screen coordinates so client and
+                // screen coordinates are the same.
+                Assert.Equal(new PixelPoint(10, 10), popupParent.PointToScreen(new Point(10, 10)));
+
+                // The event will be raised on the popup content at 50,50 (90,90 in screen coordinates)
+                var pointer = new Pointer(Pointer.GetNextFreeId(), PointerType.Mouse, true);
+                var ev = new PointerPressedEventArgs(
+                    popupContent,
+                    pointer,
+                    popupContent.VisualRoot as PopupRoot,
+                    new Point(50 , 50),
+                    0,
+                    new PointerPointProperties(RawInputModifiers.None, PointerUpdateKind.LeftButtonPressed),
+                    KeyModifiers.None);
+
+                var contentRaised = 0;
+                var parentRaised = 0;
+
+                // The event is raised on the popup content in popup coordinates.
+                popupContent.AddHandler(Button.PointerPressedEvent, (s, e) =>
+                {
+                    ++contentRaised;
+                    Assert.Equal(new Point(50, 50), e.GetPosition(popupContent));
+                });
+
+                // The event is raised on the parent in root coordinates (which in this case are 
+                // the same as screen coordinates).
+                popupParent.AddHandler(Button.PointerPressedEvent, (s, e) =>
+                {
+                    ++parentRaised;
+                    Assert.Equal(new Point(90, 90), e.GetPosition(popupParent));
+                });
+
+                popupContent.RaiseEvent(ev);
+
+                Assert.Equal(1, contentRaised);
+                Assert.Equal(1, parentRaised);
+            }
+        }
+
+        private static PopupRoot CreateRoot(TopLevel popupParent, IPopupImpl impl = null)
+        {
+            impl ??= popupParent.PlatformImpl.CreatePopup();
+
+            var result = new PopupRoot(popupParent, impl)
+            {
+                Template = new FuncControlTemplate<PopupRoot>((parent, scope) =>
+                    new ContentPresenter
                     {
-                        if(UsePopupHost)
-                            return null;
-                        return MockWindowingPlatform.CreatePopupMock(x).Object;
-                    })));
+                        Name = "PART_ContentPresenter",
+                        [!ContentPresenter.ContentProperty] = parent[!PopupRoot.ContentProperty],
+                    }.RegisterInNameScope(scope)),
+            };
+
+            result.ApplyTemplate();
+
+            return result;
+        }
+
+        private IDisposable CreateServices()
+        {
+            return UnitTestApplication.Start(TestServices.StyledWindow.With(
+                windowingPlatform: CreateMockWindowingPlatform()));
         }
 
         private IDisposable CreateServicesWithFocus()
         {
-            return UnitTestApplication.Start(TestServices.StyledWindow.With(windowingPlatform:
-                new MockWindowingPlatform(null,
-                    x =>
-                    {
-                        if (UsePopupHost)
-                            return null;
-                        return MockWindowingPlatform.CreatePopupMock(x).Object;
-                    }), 
-                    focusManager: new FocusManager(),
-                    keyboardDevice: () => new KeyboardDevice()));
+            return UnitTestApplication.Start(TestServices.StyledWindow.With(
+                windowingPlatform: CreateMockWindowingPlatform(),
+                focusManager: new FocusManager(),
+                keyboardDevice: () => new KeyboardDevice()));
         }
 
        
@@ -1116,6 +1189,23 @@ namespace Avalonia.Controls.UnitTests.Primitives
                 KeyModifiers.None);
         }
 
+        private MockWindowingPlatform CreateMockWindowingPlatform()
+        {
+            return new MockWindowingPlatform(() =>
+            {
+                var mock = MockWindowingPlatform.CreateWindowMock();
+                
+                mock.Setup(x => x.CreatePopup()).Returns(() =>
+                {
+                    if (UsePopupHost)
+                        return null;
+                    return MockWindowingPlatform.CreatePopupMock(mock.Object).Object;
+                });
+
+                return mock.Object;
+            }, null);
+        }
+
         private static Window PreparedWindow(object content = null)
         {
             var w = new Window { Content = content };
diff --git a/tests/Avalonia.Controls.UnitTests/Primitives/SelectingItemsControlTests.cs b/tests/Avalonia.Controls.UnitTests/Primitives/SelectingItemsControlTests.cs
index 51745e1687..e456f25238 100644
--- a/tests/Avalonia.Controls.UnitTests/Primitives/SelectingItemsControlTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/Primitives/SelectingItemsControlTests.cs
@@ -28,7 +28,7 @@ using Xunit;
 
 namespace Avalonia.Controls.UnitTests.Primitives
 {
-    public partial class SelectingItemsControlTests
+    public partial class SelectingItemsControlTests : ScopedTestBase
     {
         private MouseTestHelper _helper = new MouseTestHelper();
 
diff --git a/tests/Avalonia.Controls.UnitTests/ScrollViewerTests.cs b/tests/Avalonia.Controls.UnitTests/ScrollViewerTests.cs
index 9a7d51d86d..a7628cf243 100644
--- a/tests/Avalonia.Controls.UnitTests/ScrollViewerTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/ScrollViewerTests.cs
@@ -13,7 +13,7 @@ using Xunit;
 
 namespace Avalonia.Controls.UnitTests
 {
-    public class ScrollViewerTests
+    public class ScrollViewerTests : ScopedTestBase
     {
         private readonly MouseTestHelper _mouse = new();
 
@@ -440,7 +440,7 @@ namespace Avalonia.Controls.UnitTests
             throw new InvalidOperationException("Could not get the point in root coordinates.");
         }
 
-        private Control CreateTemplate(ScrollViewer control, INameScope scope)
+        internal static Control CreateTemplate(ScrollViewer control, INameScope scope)
         {
             return new Grid
             {
@@ -480,7 +480,7 @@ namespace Avalonia.Controls.UnitTests
             };
         }
 
-        private Control CreateScrollBarTemplate(ScrollBar scrollBar, INameScope scope)
+        private static Control CreateScrollBarTemplate(ScrollBar scrollBar, INameScope scope)
         {
             return new Border
             {
diff --git a/tests/Avalonia.Controls.UnitTests/TabControlTests.cs b/tests/Avalonia.Controls.UnitTests/TabControlTests.cs
index 398ac3ff43..7721018453 100644
--- a/tests/Avalonia.Controls.UnitTests/TabControlTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/TabControlTests.cs
@@ -272,28 +272,28 @@ namespace Avalonia.Controls.UnitTests
 
             ApplyTemplate(target);
 
-            ((ContentPresenter)target.ContentPart).UpdateChild();
+            target.ContentPart.UpdateChild();
             var dataContext = ((TextBlock)target.ContentPart.Child).DataContext;
             Assert.Equal(items[0], dataContext);
 
             target.SelectedIndex = 1;
-            ((ContentPresenter)target.ContentPart).UpdateChild();
+            target.ContentPart.UpdateChild();
             dataContext = ((Button)target.ContentPart.Child).DataContext;
             Assert.Equal(items[1], dataContext);
 
             target.SelectedIndex = 2;
-            ((ContentPresenter)target.ContentPart).UpdateChild();
+            target.ContentPart.UpdateChild();
             dataContext = ((TextBlock)target.ContentPart.Child).DataContext;
             Assert.Equal("Base", dataContext);
 
             target.SelectedIndex = 3;
-            ((ContentPresenter)target.ContentPart).UpdateChild();
+            target.ContentPart.UpdateChild();
             dataContext = ((TextBlock)target.ContentPart.Child).DataContext;
             Assert.Equal("Qux", dataContext);
 
             target.SelectedIndex = 4;
-            ((ContentPresenter)target.ContentPart).UpdateChild();
-            dataContext = ((Control)target.ContentPart).DataContext;
+            target.ContentPart.UpdateChild();
+            dataContext = target.ContentPart.DataContext;
             Assert.Equal("Base", dataContext);
         }
 
@@ -367,7 +367,7 @@ namespace Avalonia.Controls.UnitTests
             var root = new TestRoot(target);
 
             ApplyTemplate(target);
-            ((ContentPresenter)target.ContentPart).UpdateChild();
+            target.ContentPart.UpdateChild();
 
             var content = Assert.IsType<TextBlock>(target.ContentPart.Child);
             Assert.Equal("bar", content.Tag);
@@ -375,6 +375,27 @@ namespace Avalonia.Controls.UnitTests
             Assert.Single(target.GetLogicalChildren(), content);
         }
 
+        [Fact]
+        public void SelectedContentTemplate_Updates_After_New_ContentTemplate()
+        {
+            TabControl target = new TabControl
+            {
+                Template = TabControlTemplate(),
+                ItemsSource = new[] { "Foo" },
+            };
+            var root = new TestRoot(target);
+
+            ApplyTemplate(target);
+            ((ContentPresenter)target.ContentPart).UpdateChild();
+
+            Assert.Equal(null, Assert.IsType<TextBlock>(target.ContentPart.Child).Tag);
+
+            target.ContentTemplate = new FuncDataTemplate<string>((x, _) =>
+                    new TextBlock { Tag = "bar", Text = x });
+
+            Assert.Equal("bar", Assert.IsType<TextBlock>(target.ContentPart.Child).Tag);
+        }
+
         [Fact]
         public void Should_Not_Propagate_DataContext_To_TabItem_Content()
         {
@@ -587,7 +608,7 @@ namespace Avalonia.Controls.UnitTests
 
                 tabItem.ApplyTemplate();
 
-                ((ContentPresenter)tabItem.Presenter).UpdateChild();
+                tabItem.Presenter.UpdateChild();
             }
 
             target.ContentPart.ApplyTemplate();
diff --git a/tests/Avalonia.Controls.UnitTests/TextBoxTests.cs b/tests/Avalonia.Controls.UnitTests/TextBoxTests.cs
index 0d559557fe..d4558c9e04 100644
--- a/tests/Avalonia.Controls.UnitTests/TextBoxTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/TextBoxTests.cs
@@ -13,6 +13,7 @@ using Avalonia.Layout;
 using Avalonia.Media;
 using Avalonia.Platform;
 using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
 using Avalonia.UnitTests;
 using Moq;
 using Xunit;
@@ -884,7 +885,7 @@ namespace Avalonia.Controls.UnitTests
                     Template = CreateTemplate(),
                     Text = "ABC",
                     MaxLines = 1,
-                    AcceptsReturn= true
+                    AcceptsReturn = true
                 };
 
                 var impl = CreateMockTopLevelImpl();
@@ -896,8 +897,11 @@ namespace Avalonia.Controls.UnitTests
                 topLevel.ApplyTemplate();
                 topLevel.LayoutManager.ExecuteInitialLayoutPass();
 
+                target.ApplyTemplate();
                 target.Measure(Size.Infinity);
 
+                var initialHeight = target.DesiredSize.Height;
+
                 topLevel.Clipboard?.SetTextAsync(Environment.NewLine).GetAwaiter().GetResult();
 
                 RaiseKeyEvent(target, Key.V, KeyModifiers.Control);
@@ -905,7 +909,10 @@ namespace Avalonia.Controls.UnitTests
 
                 RaiseTextEvent(target, Environment.NewLine);
 
-                Assert.Equal("ABC", target.Text);
+                target.InvalidateMeasure();
+                target.Measure(Size.Infinity);
+
+                Assert.Equal(initialHeight, target.DesiredSize.Height);
             }
         }
 
@@ -1116,7 +1123,11 @@ namespace Avalonia.Controls.UnitTests
         private IControlTemplate CreateTemplate()
         {
             return new FuncControlTemplate<TextBox>((control, scope) =>
-                new TextPresenter
+            new ScrollViewer
+            {
+                Name = "Part_ScrollViewer",
+                Template = new FuncControlTemplate<ScrollViewer>(ScrollViewerTests.CreateTemplate),
+                Content = new TextPresenter
                 {
                     Name = "PART_TextPresenter",
                     [!!TextPresenter.TextProperty] = new Binding
@@ -1133,7 +1144,8 @@ namespace Avalonia.Controls.UnitTests
                         Priority = BindingPriority.Template,
                         RelativeSource = new RelativeSource(RelativeSourceMode.TemplatedParent),
                     }
-                }.RegisterInNameScope(scope));
+                }.RegisterInNameScope(scope)
+            }.RegisterInNameScope(scope));
         }
 
         private static void RaiseKeyEvent(TextBox textBox, Key key, KeyModifiers inputModifiers)
@@ -1214,8 +1226,7 @@ namespace Avalonia.Controls.UnitTests
         private static Mock<ITopLevelImpl> CreateMockTopLevelImpl()
         {
             var clipboard = new Mock<ITopLevelImpl>();
-            clipboard.Setup(r => r.CreateRenderer(It.IsAny<IRenderRoot>()))
-                .Returns(RendererMocks.CreateRenderer().Object);
+            clipboard.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
             clipboard.Setup(r => r.TryGetFeature(typeof(IClipboard)))
                 .Returns(new ClipboardStub());
             clipboard.SetupGet(x => x.RenderScaling).Returns(1);
diff --git a/tests/Avalonia.Controls.UnitTests/TopLevelTests.cs b/tests/Avalonia.Controls.UnitTests/TopLevelTests.cs
index 1c7935e167..a611992ab8 100644
--- a/tests/Avalonia.Controls.UnitTests/TopLevelTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/TopLevelTests.cs
@@ -8,6 +8,7 @@ using Avalonia.Layout;
 using Avalonia.LogicalTree;
 using Avalonia.Platform;
 using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
 using Avalonia.Styling;
 using Avalonia.UnitTests;
 using Moq;
@@ -136,8 +137,7 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var impl = CreateMockTopLevelImpl();
-                impl.SetupAllProperties();
+                var impl = CreateMockTopLevelImpl(true);
                 impl.Setup(x => x.ClientSize).Returns(new Size(123, 456));
 
                 // The user has resized the window, so we can no longer auto-size.
@@ -154,8 +154,7 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var impl = CreateMockTopLevelImpl();
-                impl.SetupAllProperties();
+                var impl = CreateMockTopLevelImpl(true);
 
                 bool raised = false;
                 var target = new TestTopLevel(impl.Object);
@@ -172,8 +171,7 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var impl = CreateMockTopLevelImpl();
-                impl.SetupAllProperties();
+                var impl = CreateMockTopLevelImpl(true);
 
                 var target = new TestTopLevel(impl.Object);
                 var raised = 0;
@@ -203,8 +201,7 @@ namespace Avalonia.Controls.UnitTests
 
             using (UnitTestApplication.Start(services))
             {
-                var impl = CreateMockTopLevelImpl();
-                impl.SetupAllProperties();
+                var impl = CreateMockTopLevelImpl(true);
 
                 var target = new TestTopLevel(impl.Object);
 
@@ -225,8 +222,7 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var impl = CreateMockTopLevelImpl();
-                impl.SetupAllProperties();
+                var impl = CreateMockTopLevelImpl(true);
                 var target = new TestTopLevel(impl.Object);
                 var child = new TestTopLevel(impl.Object);
 
@@ -243,8 +239,7 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var impl = CreateMockTopLevelImpl();
-                impl.SetupAllProperties();
+                var impl = CreateMockTopLevelImpl(true);
                 var target = new TestTopLevel(impl.Object);
                 var raised = false;
 
@@ -260,8 +255,7 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var impl = CreateMockTopLevelImpl();
-                impl.SetupAllProperties();
+                var impl = CreateMockTopLevelImpl(true);
 
                 var layoutManager = new Mock<ILayoutManager>();
                 var target = new TestTopLevel(impl.Object, layoutManager.Object);
@@ -320,12 +314,14 @@ namespace Avalonia.Controls.UnitTests
                 }.RegisterInNameScope(scope));
         }
 
-        private static Mock<ITopLevelImpl> CreateMockTopLevelImpl()
+        private static Mock<ITopLevelImpl> CreateMockTopLevelImpl(bool setupProperties = false)
         {
-            var renderer = new Mock<ITopLevelImpl>();
-            renderer.Setup(r => r.CreateRenderer(It.IsAny<IRenderRoot>()))
-                .Returns(RendererMocks.CreateRenderer().Object);
-            return renderer;
+            var topLevel = new Mock<ITopLevelImpl>();
+            if (setupProperties)
+                topLevel.SetupAllProperties();
+            topLevel.Setup(x => x.RenderScaling).Returns(1);
+            topLevel.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
+            return topLevel;
         }
 
         private class TestTopLevel : TopLevel
diff --git a/tests/Avalonia.Controls.UnitTests/TreeViewTests.cs b/tests/Avalonia.Controls.UnitTests/TreeViewTests.cs
index 604ff1c715..f4306f63db 100644
--- a/tests/Avalonia.Controls.UnitTests/TreeViewTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/TreeViewTests.cs
@@ -23,7 +23,7 @@ using Xunit;
 
 namespace Avalonia.Controls.UnitTests
 {
-    public class TreeViewTests
+    public class TreeViewTests : ScopedTestBase
     {
         private readonly MouseTestHelper _mouse = new();
 
diff --git a/tests/Avalonia.Controls.UnitTests/VirtualizingStackPanelTests.cs b/tests/Avalonia.Controls.UnitTests/VirtualizingStackPanelTests.cs
index c5a6ecc376..4be888f96d 100644
--- a/tests/Avalonia.Controls.UnitTests/VirtualizingStackPanelTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/VirtualizingStackPanelTests.cs
@@ -19,7 +19,7 @@ using Xunit;
 
 namespace Avalonia.Controls.UnitTests
 {
-    public class VirtualizingStackPanelTests
+    public class VirtualizingStackPanelTests : ScopedTestBase
     {
         [Fact]
         public void Creates_Initial_Items()
diff --git a/tests/Avalonia.Controls.UnitTests/WindowBaseTests.cs b/tests/Avalonia.Controls.UnitTests/WindowBaseTests.cs
index d65fa06183..1c6495359a 100644
--- a/tests/Avalonia.Controls.UnitTests/WindowBaseTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/WindowBaseTests.cs
@@ -7,8 +7,10 @@ using Avalonia.Controls.Templates;
 using Avalonia.Input;
 using Avalonia.Input.Raw;
 using Avalonia.Layout;
+using Avalonia.Media;
 using Avalonia.Platform;
 using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
 using Avalonia.Styling;
 using Avalonia.UnitTests;
 using Xunit;
@@ -36,8 +38,7 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var impl = CreateMockWindowBaseImpl();
-                impl.SetupAllProperties();
+                var impl = CreateMockWindowBaseImpl(true);
 
                 bool raised = false;
                 var target = new TestWindowBase(impl.Object);
@@ -55,8 +56,7 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var impl = CreateMockWindowBaseImpl();
-                impl.SetupAllProperties();
+                var impl = CreateMockWindowBaseImpl(true);
 
                 bool raised = false;
                 var target = new TestWindowBase(impl.Object);
@@ -110,8 +110,7 @@ namespace Avalonia.Controls.UnitTests
         public void IsVisible_Should_Be_False_Atfer_Impl_Signals_Close()
         {
             var windowImpl = new Mock<IPopupImpl>();
-            windowImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>()))
-                .Returns(() => RendererMocks.CreateRenderer().Object);
+            windowImpl.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
             windowImpl.Setup(x => x.DesktopScaling).Returns(1);
             windowImpl.Setup(x => x.RenderScaling).Returns(1);
             windowImpl.SetupProperty(x => x.Closed);
@@ -131,8 +130,7 @@ namespace Avalonia.Controls.UnitTests
         public void Setting_IsVisible_True_Shows_Window()
         {
             var windowImpl = new Mock<IPopupImpl>();
-            windowImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>()))
-                .Returns(() => RendererMocks.CreateRenderer().Object);
+            windowImpl.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
             windowImpl.Setup(x => x.DesktopScaling).Returns(1);
             windowImpl.Setup(x => x.RenderScaling).Returns(1);
 
@@ -149,8 +147,7 @@ namespace Avalonia.Controls.UnitTests
         public void Setting_IsVisible_False_Hides_Window()
         {
             var windowImpl = new Mock<IPopupImpl>();
-            windowImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>()))
-                .Returns(() => RendererMocks.CreateRenderer().Object);
+            windowImpl.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
             windowImpl.Setup(x => x.DesktopScaling).Returns(1);
             windowImpl.Setup(x => x.RenderScaling).Returns(1);
 
@@ -169,12 +166,11 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var renderer = RendererMocks.CreateRenderer();
-                var target = new TestWindowBase(renderer.Object);
+                var target = new TestWindowBase();
 
                 target.Show();
 
-                renderer.Verify(x => x.Start(), Times.Once);
+                Assert.True(MediaContext.Instance.IsTopLevelActive(target));
             }
         }
 
@@ -200,13 +196,12 @@ namespace Avalonia.Controls.UnitTests
 
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var renderer = RendererMocks.CreateRenderer();
-                var target = new TestWindowBase(renderer.Object);
+                var target = new TestWindowBase();
 
                 target.Show();
                 target.Hide();
 
-                renderer.Verify(x => x.Stop(), Times.Once);
+                Assert.False(MediaContext.Instance.IsTopLevelActive(target));
             }
         }
 
@@ -215,19 +210,17 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var renderer = RendererMocks.CreateRenderer();
                 var windowImpl = new Mock<IPopupImpl>();
                 windowImpl.Setup(x => x.DesktopScaling).Returns(1);
                 windowImpl.Setup(x => x.RenderScaling).Returns(1);
                 windowImpl.SetupProperty(x => x.Closed);
-                windowImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>())).Returns(renderer.Object);
+                windowImpl.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
 
                 var target = new TestWindowBase(windowImpl.Object);
 
                 target.Show();
                 windowImpl.Object.Closed();
-
-                renderer.Verify(x => x.Dispose(), Times.Once);
+                Assert.True(((CompositingRenderer)target.Renderer).IsDisposed);
             }
         }
 
@@ -241,11 +234,12 @@ namespace Avalonia.Controls.UnitTests
                 }.RegisterInNameScope(scope));
         }
 
-        private static Mock<IWindowBaseImpl> CreateMockWindowBaseImpl()
+        private static Mock<IWindowBaseImpl> CreateMockWindowBaseImpl(bool setupAllProperties = false)
         {
             var renderer = new Mock<IWindowBaseImpl>();
-            renderer.Setup(r => r.CreateRenderer(It.IsAny<IRenderRoot>()))
-                .Returns(RendererMocks.CreateRenderer().Object);
+            if (setupAllProperties)
+                renderer.SetupAllProperties();
+            renderer.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
             return renderer;
         }
 
@@ -253,15 +247,18 @@ namespace Avalonia.Controls.UnitTests
         {
             public bool IsClosed { get; private set; }
 
-            public TestWindowBase(IRenderer renderer = null)
-                : base(CreateWindowsBaseImplMock(renderer ?? RendererMocks.CreateRenderer().Object))
+            public TestWindowBase()
+                : base(CreateWindowsBaseImplMock())
             {
             }
 
-            private static IWindowBaseImpl CreateWindowsBaseImplMock(IRenderer renderer)
-                => Mock.Of<IWindowBaseImpl>(x =>
+            private static IWindowBaseImpl CreateWindowsBaseImplMock()
+            {
+                var compositor = RendererMocks.CreateDummyCompositor();
+                return Mock.Of<IWindowBaseImpl>(x =>
                     x.RenderScaling == 1 &&
-                    x.CreateRenderer(It.IsAny<IRenderRoot>()) == renderer);
+                    x.Compositor == compositor);
+            }
 
             public TestWindowBase(IWindowBaseImpl impl)
                 : base(impl)
diff --git a/tests/Avalonia.Controls.UnitTests/WindowTests.cs b/tests/Avalonia.Controls.UnitTests/WindowTests.cs
index b59f6e03f7..cd45a3d920 100644
--- a/tests/Avalonia.Controls.UnitTests/WindowTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/WindowTests.cs
@@ -1,8 +1,10 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using Avalonia.Media;
 using Avalonia.Platform;
 using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
 using Avalonia.UnitTests;
 using Moq;
 using Xunit;
@@ -15,8 +17,7 @@ namespace Avalonia.Controls.UnitTests
         public void Setting_Title_Should_Set_Impl_Title()
         {
             var windowImpl = new Mock<IWindowImpl>();
-            windowImpl.Setup(r => r.CreateRenderer(It.IsAny<IRenderRoot>()))
-                .Returns(RendererMocks.CreateRenderer().Object);
+            windowImpl.Setup(r => r.Compositor).Returns(RendererMocks.CreateDummyCompositor());
             var windowingPlatform = new MockWindowingPlatform(() => windowImpl.Object);
 
             using (UnitTestApplication.Start(new TestServices(windowingPlatform: windowingPlatform)))
@@ -100,8 +101,7 @@ namespace Avalonia.Controls.UnitTests
         public void IsVisible_Should_Be_False_After_Impl_Signals_Close()
         {
             var windowImpl = new Mock<IWindowImpl>();
-            windowImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>()))
-                .Returns(() => RendererMocks.CreateRenderer().Object);
+            windowImpl.Setup(r => r.Compositor).Returns(RendererMocks.CreateDummyCompositor());
             windowImpl.SetupProperty(x => x.Closed);
             windowImpl.Setup(x => x.DesktopScaling).Returns(1);
             windowImpl.Setup(x => x.RenderScaling).Returns(1);
@@ -273,12 +273,10 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var renderer = RendererMocks.CreateRenderer();
-                var target = new Window(CreateImpl(renderer));
+                var target = new Window(CreateImpl());
 
                 target.Show();
-
-                renderer.Verify(x => x.Start(), Times.Once);
+                Assert.True(MediaContext.Instance.IsTopLevelActive(target));
             }
         }
 
@@ -288,13 +286,12 @@ namespace Avalonia.Controls.UnitTests
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
                 var parent = new Window();
-                var renderer = RendererMocks.CreateRenderer();
-                var target = new Window(CreateImpl(renderer));
+                var target = new Window(CreateImpl());
 
                 parent.Show();
                 target.ShowDialog<object>(parent);
 
-                renderer.Verify(x => x.Start(), Times.Once);
+                Assert.True(MediaContext.Instance.IsTopLevelActive(target));
             }
         }
 
@@ -321,13 +318,11 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var renderer = RendererMocks.CreateRenderer();
-                var target = new Window(CreateImpl(renderer));
+                var target = new Window(CreateImpl());
 
                 target.Show();
                 target.Hide();
-
-                renderer.Verify(x => x.Stop(), Times.Once);
+                Assert.False(MediaContext.Instance.IsTopLevelActive(target));
             }
         }
 
@@ -338,8 +333,7 @@ namespace Avalonia.Controls.UnitTests
             {
                 var parent = new Window();
                 var windowImpl = new Mock<IWindowImpl>();
-                windowImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>()))
-                    .Returns(() => RendererMocks.CreateRenderer().Object);
+                windowImpl.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
                 windowImpl.SetupProperty(x => x.Closed);
                 windowImpl.Setup(x => x.DesktopScaling).Returns(1);
                 windowImpl.Setup(x => x.RenderScaling).Returns(1);
@@ -381,8 +375,7 @@ namespace Avalonia.Controls.UnitTests
             {
                 var parent = new Window();
                 var windowImpl = new Mock<IWindowImpl>();
-                windowImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>()))
-                    .Returns(() => RendererMocks.CreateRenderer().Object);
+                windowImpl.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
                 windowImpl.SetupProperty(x => x.Closed);
                 windowImpl.Setup(x => x.DesktopScaling).Returns(1);
                 windowImpl.Setup(x => x.RenderScaling).Returns(1);
@@ -1054,11 +1047,11 @@ namespace Avalonia.Controls.UnitTests
             }
         }
 
-        private static IWindowImpl CreateImpl(Mock<IRenderer> renderer)
+        private static IWindowImpl CreateImpl()
         {
-            return Mock.Of<IWindowImpl>(x =>
-                x.RenderScaling == 1 &&
-                x.CreateRenderer(It.IsAny<IRenderRoot>()) == renderer.Object);
+            var compositor = RendererMocks.CreateDummyCompositor();
+            return Mock.Of<IWindowImpl>(x => x.RenderScaling == 1 &&
+                                             x.Compositor == compositor);
         }
 
         private class ChildControl : Control
diff --git a/tests/Avalonia.LeakTests/ControlTests.cs b/tests/Avalonia.LeakTests/ControlTests.cs
index b3a6b52d68..ab8e4377b6 100644
--- a/tests/Avalonia.LeakTests/ControlTests.cs
+++ b/tests/Avalonia.LeakTests/ControlTests.cs
@@ -16,6 +16,7 @@ using Avalonia.Input;
 using Avalonia.Media;
 using Avalonia.Platform;
 using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
 using Avalonia.Styling;
 using Avalonia.Threading;
 using Avalonia.UnitTests;
@@ -462,13 +463,11 @@ namespace Avalonia.LeakTests
         {
             using (Start())
             {
-                var renderer = RendererMocks.CreateRenderer();
-                renderer.Setup(x => x.Dispose());
                 var impl = new Mock<IWindowImpl>();
                 impl.Setup(r => r.TryGetFeature(It.IsAny<Type>())).Returns(null);
                 impl.SetupGet(x => x.RenderScaling).Returns(1);
                 impl.SetupProperty(x => x.Closed);
-                impl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>())).Returns(renderer.Object);
+                impl.Setup(x => x.Compositor).Returns(RendererMocks.CreateDummyCompositor());
                 impl.Setup(x => x.Dispose()).Callback(() => impl.Object.Closed());
 
                 AvaloniaLocator.CurrentMutable.Bind<IWindowingPlatform>()
@@ -479,7 +478,7 @@ namespace Avalonia.LeakTests
                 };
                 window.Show();
                 window.Close();
-                renderer.Verify(r => r.Dispose());
+                Assert.True(((CompositingRenderer)window.Renderer).IsDisposed);
             }
         }
 
diff --git a/tests/Avalonia.Markup.Xaml.UnitTests/Converters/AvaloniaPropertyConverterTest.cs b/tests/Avalonia.Markup.Xaml.UnitTests/Converters/AvaloniaPropertyConverterTest.cs
index 241ebc2d38..52efc62018 100644
--- a/tests/Avalonia.Markup.Xaml.UnitTests/Converters/AvaloniaPropertyConverterTest.cs
+++ b/tests/Avalonia.Markup.Xaml.UnitTests/Converters/AvaloniaPropertyConverterTest.cs
@@ -8,7 +8,7 @@ using Xunit;
 
 namespace Avalonia.Markup.Xaml.UnitTests.Converters
 {
-    public class AvaloniaPropertyConverterTest
+    public class AvaloniaPropertyConverterTest : XamlTestBase
     {
         public AvaloniaPropertyConverterTest()
         {
diff --git a/tests/Avalonia.Markup.Xaml.UnitTests/Converters/PointsListTypeConverterTests.cs b/tests/Avalonia.Markup.Xaml.UnitTests/Converters/PointsListTypeConverterTests.cs
index 4dada1313e..6664c374bc 100644
--- a/tests/Avalonia.Markup.Xaml.UnitTests/Converters/PointsListTypeConverterTests.cs
+++ b/tests/Avalonia.Markup.Xaml.UnitTests/Converters/PointsListTypeConverterTests.cs
@@ -7,7 +7,7 @@ using Xunit;
 
 namespace Avalonia.Markup.Xaml.UnitTests.Converters
 {
-    public class PointsListTypeConverterTests
+    public class PointsListTypeConverterTests : XamlTestBase
     {
         static PointsListTypeConverterTests()
         {
diff --git a/tests/Avalonia.Markup.Xaml.UnitTests/MarkupExtensions/CompiledBindingExtensionTests.cs b/tests/Avalonia.Markup.Xaml.UnitTests/MarkupExtensions/CompiledBindingExtensionTests.cs
index 7ed43efd94..9d82674fb6 100644
--- a/tests/Avalonia.Markup.Xaml.UnitTests/MarkupExtensions/CompiledBindingExtensionTests.cs
+++ b/tests/Avalonia.Markup.Xaml.UnitTests/MarkupExtensions/CompiledBindingExtensionTests.cs
@@ -472,7 +472,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.MarkupExtensions
 
                 window.ApplyTemplate();
                 target.ApplyTemplate();
-                ((ContentPresenter)target.Presenter).UpdateChild();
+                target.Presenter.UpdateChild();
 
                 Assert.Equal(dataContext.StringProperty, ((TextBlock)target.Presenter.Child).Text);
             }
@@ -694,7 +694,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.MarkupExtensions
 
                 window.ApplyTemplate();
                 target.ApplyTemplate();
-                ((ContentPresenter)target.Presenter).UpdateChild();
+                target.Presenter.UpdateChild();
 
                 Assert.Equal(dataContext.StringProperty, ((TextBlock)target.Presenter.Child).Text);
             }
@@ -727,7 +727,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.MarkupExtensions
 
                 window.ApplyTemplate();
                 target.ApplyTemplate();
-                ((ContentPresenter)target.Presenter).UpdateChild();
+                target.Presenter.UpdateChild();
 
                 Assert.Equal(dataContext.StringProperty, ((TextBlock)target.Presenter.Child).Text);
             }
@@ -760,7 +760,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.MarkupExtensions
 
                 window.ApplyTemplate();
                 target.ApplyTemplate();
-                ((ContentPresenter)target.Presenter).UpdateChild();
+                target.Presenter.UpdateChild();
 
                 Assert.Equal(dataContext.StringProperty, ((TextBlock)target.Presenter.Child).Text);
             }
diff --git a/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/ControlTemplateTests.cs b/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/ControlTemplateTests.cs
index 4404564733..ea2407e18d 100644
--- a/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/ControlTemplateTests.cs
+++ b/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/ControlTemplateTests.cs
@@ -74,7 +74,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 window.ApplyTemplate();
                 button.ApplyTemplate();
 
-                var presenter = (ContentPresenter)button.Presenter;
+                var presenter = button.Presenter;
                 Assert.Equal(Brushes.Red, presenter.Background);
 
                 var diagnostic = presenter.GetDiagnostic(Button.BackgroundProperty);
@@ -108,7 +108,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 window.ApplyTemplate();
                 button.ApplyTemplate();
 
-                var presenter = (ContentPresenter)button.Presenter;
+                var presenter = button.Presenter;
                 Assert.Equal(Brushes.Red, presenter.Background);
 
                 var diagnostic = presenter.GetDiagnostic(Button.BackgroundProperty);
@@ -139,7 +139,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 window.ApplyTemplate();
                 button.ApplyTemplate();
 
-                var presenter = (ContentPresenter)button.Presenter;
+                var presenter = button.Presenter;
                 Assert.Equal(Dock.Top, DockPanel.GetDock(presenter));
 
                 var diagnostic = presenter.GetDiagnostic(DockPanel.DockProperty);
@@ -173,7 +173,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 window.ApplyTemplate();
                 button.ApplyTemplate();
 
-                var presenter = (ContentPresenter)button.Presenter;
+                var presenter = button.Presenter;
                 Assert.Equal(Brushes.Red, presenter.Background);
 
                 var diagnostic = presenter.GetDiagnostic(Button.BackgroundProperty);
@@ -207,7 +207,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 window.ApplyTemplate();
                 button.ApplyTemplate();
 
-                var presenter = (ContentPresenter)button.Presenter;
+                var presenter = button.Presenter;
                 Assert.Equal(Brushes.Red, presenter.Background);
 
                 var diagnostic = presenter.GetDiagnostic(Button.BackgroundProperty);
@@ -238,7 +238,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 window.ApplyTemplate();
                 button.ApplyTemplate();
 
-                var presenter = (ContentPresenter)button.Presenter;
+                var presenter = button.Presenter;
                 Assert.Equal("Foo", presenter.Content);
 
                 var diagnostic = presenter.GetDiagnostic(ContentPresenter.ContentProperty);
diff --git a/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/ControlThemeTests.cs b/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/ControlThemeTests.cs
index 1e4c89b33a..e153f1112a 100644
--- a/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/ControlThemeTests.cs
+++ b/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/ControlThemeTests.cs
@@ -28,7 +28,6 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 var button = Assert.IsType<TestTemplatedControl>(window.Content);
 
                 window.Show();
-                window.LayoutManager.ExecuteInitialLayoutPass();
 
                 Assert.NotNull(button.Template);
 
@@ -65,7 +64,6 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 var button = Assert.IsType<TestTemplatedControl>(window.Content);
 
                 window.Show();
-                window.LayoutManager.ExecuteInitialLayoutPass();
 
                 Assert.NotNull(button.Template);
 
diff --git a/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/DataTemplateTests.cs b/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/DataTemplateTests.cs
index 05e81dc0ba..89416ad674 100644
--- a/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/DataTemplateTests.cs
+++ b/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/DataTemplateTests.cs
@@ -32,7 +32,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
 
                 window.ApplyTemplate();
                 target.ApplyTemplate();
-                ((ContentPresenter)target.Presenter).UpdateChild();
+                target.Presenter.UpdateChild();
 
                 Assert.Null(target.Presenter.Child);
             }
@@ -59,7 +59,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
 
                 window.ApplyTemplate();
                 target.ApplyTemplate();
-                ((ContentPresenter)target.Presenter).UpdateChild();
+                target.Presenter.UpdateChild();
 
                 Assert.IsType<Canvas>(target.Presenter.Child);
             }
@@ -117,7 +117,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 
                 window.ApplyTemplate();
                 target.ApplyTemplate();
-                ((ContentPresenter)target.Presenter).UpdateChild();
+                target.Presenter.UpdateChild();
                 
                 Assert.Equal(typeof(string), template.DataType);
                 Assert.IsType<Canvas>(target.Presenter.Child);
@@ -145,7 +145,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
 
                 window.ApplyTemplate();
                 target.ApplyTemplate();
-                ((ContentPresenter)target.Presenter).UpdateChild();
+                target.Presenter.UpdateChild();
 
                 Assert.IsType<Canvas>(target.Presenter.Child);
             }
@@ -175,7 +175,7 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 
                 window.ApplyTemplate();
                 target.ApplyTemplate();
-                ((ContentPresenter)target.Presenter).UpdateChild();
+                target.Presenter.UpdateChild();
 
                 var dataTemplate = (CustomDataTemplate)target.ContentTemplate;
                 Assert.Null(dataTemplate.FancyDataType);
@@ -217,11 +217,11 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
 
                 window.ApplyTemplate();
                 target.ApplyTemplate();
-                ((ContentPresenter)target.Presenter).UpdateChild();
+                target.Presenter.UpdateChild();
 
                 var canvas = (Canvas)target.Presenter.Child;
                 Assert.Same(viewModel, target.DataContext);
-                Assert.Same(viewModel.Child, ((Control)target.Presenter).DataContext);
+                Assert.Same(viewModel.Child, target.Presenter.DataContext);
                 Assert.Same(viewModel.Child.Child, canvas.DataContext);
             }
         }
diff --git a/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/StyleTests.cs b/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/StyleTests.cs
index 06589beddf..b04beed48d 100644
--- a/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/StyleTests.cs
+++ b/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/StyleTests.cs
@@ -387,13 +387,13 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 Assert.Equal(new[] { Brushes.Transparent, Brushes.Green, Brushes.Transparent }, GetColors());
 
                 collection.Remove(Brushes.Green);
-                window.LayoutManager.ExecuteLayoutPass();
+                window.UpdateLayout();
 
                 Assert.Equal(new[] { Brushes.Transparent, Brushes.Blue }, GetColors());
 
                 collection.Add(Brushes.Violet);
                 collection.Add(Brushes.Black);
-                window.LayoutManager.ExecuteLayoutPass();
+                window.UpdateLayout();
 
                 Assert.Equal(new[] { Brushes.Transparent, Brushes.Blue, Brushes.Transparent, Brushes.Black }, GetColors());
             }
diff --git a/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/WindowTests.cs b/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/WindowTests.cs
new file mode 100644
index 0000000000..a48776bfee
--- /dev/null
+++ b/tests/Avalonia.Markup.Xaml.UnitTests/Xaml/WindowTests.cs
@@ -0,0 +1,26 @@
+using Avalonia.Controls;
+using Avalonia.UnitTests;
+using Xunit;
+
+namespace Avalonia.Markup.Xaml.UnitTests.Xaml
+{
+    public class WindowTests : XamlTestBase
+    {
+        [Fact]
+        public void Can_Specify_TransparencyLevelHint()
+        {
+            using var app = UnitTestApplication.Start(TestServices.MockWindowingPlatform);
+            var xaml = @"<Window xmlns='https://github.com/avaloniaui' TransparencyLevelHint='Blur,Transparent,None'/>";
+
+            var target = AvaloniaRuntimeXamlLoader.Parse<Window>(xaml);
+
+            Assert.Equal(
+                new[]
+                {
+                    WindowTransparencyLevel.Blur,
+                    WindowTransparencyLevel.Transparent,
+                    WindowTransparencyLevel.None,
+                }, target.TransparencyLevelHint);
+        }
+    }
+}
diff --git a/tests/Avalonia.Markup.Xaml.UnitTests/XamlTestBase.cs b/tests/Avalonia.Markup.Xaml.UnitTests/XamlTestBase.cs
index 26fba7ec57..0e0893fe8d 100644
--- a/tests/Avalonia.Markup.Xaml.UnitTests/XamlTestBase.cs
+++ b/tests/Avalonia.Markup.Xaml.UnitTests/XamlTestBase.cs
@@ -2,24 +2,33 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Reflection;
+using System.Runtime.CompilerServices;
 using System.Text;
 using Avalonia.Controls;
 using Avalonia.Data;
+using Avalonia.UnitTests;
 
 namespace Avalonia.Markup.Xaml.UnitTests
 {
-    public class XamlTestBase
+    static class XamlLoaderInit
     {
-        public XamlTestBase()
+        [ModuleInitializer]
+        public static void Init()
         {
-            // Ensure necessary assemblies are loaded.
             var _ = typeof(Binding);
-            GC.KeepAlive(typeof(ItemsRepeater));
+            GC.KeepAlive(typeof(ItemsRepeater).Assembly);
+        }
+    }
+    
+    public class XamlTestBase : ScopedTestBase
+    {
+        public XamlTestBase()
+        {
             if (AvaloniaLocator.Current.GetService<AvaloniaXamlLoader.IRuntimeXamlLoader>() == null)
                 AvaloniaLocator.CurrentMutable.Bind<AvaloniaXamlLoader.IRuntimeXamlLoader>()
                     .ToConstant(new TestXamlLoaderShim());
         }
-        
+
         class TestXamlLoaderShim : AvaloniaXamlLoader.IRuntimeXamlLoader
         {
             public object Load(RuntimeXamlLoaderDocument document, RuntimeXamlLoaderConfiguration configuration) 
diff --git a/tests/Avalonia.ReactiveUI.UnitTests/TransitioningContentControlTest.cs b/tests/Avalonia.ReactiveUI.UnitTests/TransitioningContentControlTest.cs
index e1ab54f775..ed96c4ef6e 100644
--- a/tests/Avalonia.ReactiveUI.UnitTests/TransitioningContentControlTest.cs
+++ b/tests/Avalonia.ReactiveUI.UnitTests/TransitioningContentControlTest.cs
@@ -22,7 +22,7 @@ namespace Avalonia.ReactiveUI.UnitTests
                 Content = "Foo"
             };
             target.ApplyTemplate();
-            ((ContentPresenter)target.Presenter).UpdateChild();
+            target.Presenter.UpdateChild();
 
             var child = ((Visual)target).GetVisualChildren().Single();
             Assert.IsType<Border>(child);
diff --git a/tests/Avalonia.RenderTests/Controls/CustomRenderTests.cs b/tests/Avalonia.RenderTests/Controls/CustomRenderTests.cs
index 7a2c60baf4..ff36877d9a 100644
--- a/tests/Avalonia.RenderTests/Controls/CustomRenderTests.cs
+++ b/tests/Avalonia.RenderTests/Controls/CustomRenderTests.cs
@@ -141,7 +141,7 @@ namespace Avalonia.Direct2D1.RenderTests.Controls
                         new Rect(control.Bounds.Size),
                         4);
 
-                    using (context.PushOpacity(0.5, control.Bounds))
+                    using (context.PushOpacity(0.5))
                     {
                         context.FillRectangle(
                             Brushes.Blue,
diff --git a/tests/Avalonia.RenderTests/TestBase.cs b/tests/Avalonia.RenderTests/TestBase.cs
index a925b4e60c..3e0ba7d2f6 100644
--- a/tests/Avalonia.RenderTests/TestBase.cs
+++ b/tests/Avalonia.RenderTests/TestBase.cs
@@ -107,25 +107,21 @@ namespace Avalonia.Direct2D1.RenderTests
             
             var timer = new ManualRenderTimer();
 
-            var compositor = new Compositor(new RenderLoop(timer, Dispatcher.UIThread), null);
+            var compositor = new Compositor(new RenderLoop(timer), null, true,
+                new DispatcherCompositorScheduler(), true);
             using (var writableBitmap = factory.CreateWriteableBitmap(pixelSize, dpiVector, factory.DefaultPixelFormat, factory.DefaultAlphaFormat))
             {
                 var root = new TestRenderRoot(dpiVector.X / 96, null!);
                 using (var renderer = new CompositingRenderer(root, compositor, () => new[]
                        {
                            new BitmapFramebufferSurface(writableBitmap)
-                       }) { RenderOnlyOnRenderThread = false })
+                       }))
                 {
                     root.Initialize(renderer, target);
                     renderer.Start();
                     Dispatcher.UIThread.RunJobs();
                     timer.TriggerTick();
                 }
-
-                // Free pools
-                for (var c = 0; c < 11; c++)
-                    foreach (var dp in Dispatcher.SnapshotTimersForUnitTests())
-                        dp.ForceFire();
                 writableBitmap.Save(compositedPath);
             }
         }
diff --git a/tests/Avalonia.RenderTests/TestRenderRoot.cs b/tests/Avalonia.RenderTests/TestRenderRoot.cs
index 8f2b324d9c..64fda9ae87 100644
--- a/tests/Avalonia.RenderTests/TestRenderRoot.cs
+++ b/tests/Avalonia.RenderTests/TestRenderRoot.cs
@@ -1,6 +1,7 @@
 using Avalonia.Rendering;
 using System.Threading.Tasks;
 using System;
+using System.Collections.Generic;
 using Avalonia.Controls;
 using Avalonia.Platform;
 
@@ -15,7 +16,9 @@ namespace Avalonia.Direct2D1.RenderTests
     {
         private readonly IRenderTarget _renderTarget;
         public Size ClientSize { get; private set; }
-        public IRenderer Renderer { get; private set; }
+        internal IRenderer Renderer { get; private set; }
+        IRenderer IRenderRoot.Renderer => Renderer;
+        IHitTester IRenderRoot.HitTester => new NullHitTester();
         public double RenderScaling { get; }
 
         public TestRenderRoot(double scaling, IRenderTarget renderTarget)
@@ -23,8 +26,15 @@ namespace Avalonia.Direct2D1.RenderTests
             _renderTarget = renderTarget;
             RenderScaling = scaling;
         }
+        
+        class NullHitTester : IHitTester
+        {
+            public IEnumerable<Visual> HitTest(Point p, Visual root, Func<Visual, bool> filter) => Array.Empty<Visual>();
+
+            public Visual HitTestFirst(Point p, Visual root, Func<Visual, bool> filter) => null;
+        }
 
-        public void Initialize(IRenderer renderer, Control child)
+        internal void Initialize(IRenderer renderer, Control child)
         {
             Renderer = renderer;
             Child = child;
diff --git a/tests/Avalonia.Skia.UnitTests/Media/TextFormatting/TextLineTests.cs b/tests/Avalonia.Skia.UnitTests/Media/TextFormatting/TextLineTests.cs
index aa5d707d0f..1d07e780e6 100644
--- a/tests/Avalonia.Skia.UnitTests/Media/TextFormatting/TextLineTests.cs
+++ b/tests/Avalonia.Skia.UnitTests/Media/TextFormatting/TextLineTests.cs
@@ -1071,6 +1071,55 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
             }
         }
 
+        [Fact]
+        public void Should_GetTextBounds_BiDi()
+        {
+            var text = "אבגדה 12345 ABCDEF אבגדה";
+
+            using (Start())
+            {
+                var defaultProperties = new GenericTextRunProperties(Typeface.Default);
+                var textSource = new SingleBufferTextSource(text, defaultProperties, true);
+
+                var formatter = new TextFormatterImpl();
+
+                var textLine =
+                    formatter.FormatLine(textSource, 0, double.PositiveInfinity,
+                        new GenericTextParagraphProperties(FlowDirection.LeftToRight, TextAlignment.Left,
+                        true, true, defaultProperties, TextWrapping.NoWrap, 0, 0, 0));
+
+                var bounds = textLine.GetTextBounds(6, 1);
+
+                Assert.Equal(1, bounds.Count);
+
+                Assert.Equal(0, bounds[0].Rectangle.Left);
+
+                bounds = textLine.GetTextBounds(5, 1);
+
+                Assert.Equal(1, bounds.Count);
+
+                Assert.Equal(36.005859374999993, bounds[0].Rectangle.Left);
+
+                bounds = textLine.GetTextBounds(0, 1);
+
+                Assert.Equal(1, bounds.Count);
+
+                Assert.Equal(71.165859375, bounds[0].Rectangle.Right);
+
+                bounds = textLine.GetTextBounds(11, 1);
+
+                Assert.Equal(1, bounds.Count);
+
+                Assert.Equal(71.165859375, bounds[0].Rectangle.Left);
+
+                bounds = textLine.GetTextBounds(0, 25);
+
+                Assert.Equal(5, bounds.Count);
+
+                Assert.Equal(textLine.WidthIncludingTrailingWhitespace, bounds.Last().Rectangle.Right);
+            }
+        }
+
         private class FixedRunsTextSource : ITextSource
         {
             private readonly IReadOnlyList<TextRun> _textRuns;
diff --git a/tests/Avalonia.UnitTests/Avalonia.UnitTests.csproj b/tests/Avalonia.UnitTests/Avalonia.UnitTests.csproj
index 0d49f78dd9..8ce0b8a984 100644
--- a/tests/Avalonia.UnitTests/Avalonia.UnitTests.csproj
+++ b/tests/Avalonia.UnitTests/Avalonia.UnitTests.csproj
@@ -22,4 +22,5 @@
   <Import Project="..\..\build\HarfBuzzSharp.props" />
   <Import Project="..\..\build\XUnit.props" />
   <Import Project="..\..\build\SharedVersion.props" />
+  <Import Project="..\..\build\AvaloniaPublicKey.props" />
 </Project>
diff --git a/tests/Avalonia.UnitTests/CompositorTestServices.cs b/tests/Avalonia.UnitTests/CompositorTestServices.cs
index de7cbc873c..0a85072af1 100644
--- a/tests/Avalonia.UnitTests/CompositorTestServices.cs
+++ b/tests/Avalonia.UnitTests/CompositorTestServices.cs
@@ -22,14 +22,14 @@ public class CompositorTestServices : IDisposable
 {
     private readonly IDisposable _app;
     public Compositor Compositor { get; }
+    internal CompositingRenderer Renderer { get; }
     public ManualRenderTimer Timer { get; } = new();
     public EmbeddableControlRoot TopLevel { get; }
-    public CompositingRenderer Renderer { get; } = null!;
     public DebugEvents Events { get; } = new();
 
     public void Dispose()
     {
-        TopLevel.Renderer.Stop();
+        TopLevel.StopRendering();
         TopLevel.Dispose();
         _app.Dispose();
     }
@@ -44,10 +44,9 @@ public class CompositorTestServices : IDisposable
         try
         {
             AvaloniaLocator.CurrentMutable.Bind<IRenderTimer>().ToConstant(Timer);
-            AvaloniaLocator.CurrentMutable.Bind<IRenderLoop>()
-                .ToConstant(new RenderLoop(Timer, Dispatcher.UIThread));
 
-            Compositor = new Compositor(AvaloniaLocator.Current.GetRequiredService<IRenderLoop>(), null);
+            Compositor = new Compositor(new RenderLoop(Timer), null,
+                true, new DispatcherCompositorScheduler(), true);
             var impl = new TopLevelImpl(Compositor, size ?? new Size(1000, 1000));
             TopLevel = new EmbeddableControlRoot(impl)
             {
@@ -61,10 +60,10 @@ public class CompositorTestServices : IDisposable
                     return presenter;
                 })
             };
-            Renderer = impl.Renderer;
             TopLevel.Prepare();
-            TopLevel.Renderer.Start();
+            TopLevel.StartRendering();
             RunJobs();
+            Renderer = ((CompositingRenderer)TopLevel.Renderer);
             Renderer.CompositionTarget.Server.DebugEvents = Events;
         }
         catch
@@ -127,13 +126,11 @@ public class CompositorTestServices : IDisposable
         public event Action<TimeSpan> Tick;
         public bool RunsInBackground => false;
         public void TriggerTick() => Tick?.Invoke(TimeSpan.Zero);
-        public Task TriggerBackgroundTick() => Task.Run(TriggerTick);
     }
 
     class TopLevelImpl : ITopLevelImpl
     {
         private readonly Compositor _compositor;
-        public CompositingRenderer Renderer { get; private set; }
 
         public TopLevelImpl(Compositor compositor, Size clientSize)
         {
@@ -166,10 +163,7 @@ public class CompositorTestServices : IDisposable
             }
         }
 
-        public IRenderer CreateRenderer(IRenderRoot root)
-        {
-            return Renderer = new CompositingRenderer(root, _compositor, () => Surfaces);
-        }
+        public Compositor Compositor => _compositor;
 
         public void Invalidate(Rect rect)
         {
@@ -192,11 +186,11 @@ public class CompositorTestServices : IDisposable
         public IMouseDevice MouseDevice { get; } = new MouseDevice();
         public IPopupImpl CreatePopup() => throw new NotImplementedException();
 
-        public void SetTransparencyLevelHint(WindowTransparencyLevel transparencyLevel)
+        public void SetTransparencyLevelHint(IReadOnlyList<WindowTransparencyLevel> transparencyLevel)
         {
         }
 
-        public WindowTransparencyLevel TransparencyLevel { get; }
+        public WindowTransparencyLevel TransparencyLevel => WindowTransparencyLevel.None;
 
         public void SetFrameThemeVariant(PlatformThemeVariant themeVariant)
         {
@@ -207,3 +201,19 @@ public class CompositorTestServices : IDisposable
         public object TryGetFeature(Type featureType) => null;
     }
 }
+
+public class NullCompositorScheduler : ICompositorScheduler
+{
+    public void CommitRequested(Compositor compositor)
+    {
+        
+    }
+}
+
+public class DispatcherCompositorScheduler : ICompositorScheduler
+{
+    public void CommitRequested(Compositor compositor)
+    {
+        Dispatcher.UIThread.Post(() => compositor.Commit(), DispatcherPriority.UiThreadRender);
+    }
+}
\ No newline at end of file
diff --git a/tests/Avalonia.UnitTests/InternalsVisibleTo.cs b/tests/Avalonia.UnitTests/InternalsVisibleTo.cs
new file mode 100644
index 0000000000..c989c25310
--- /dev/null
+++ b/tests/Avalonia.UnitTests/InternalsVisibleTo.cs
@@ -0,0 +1,11 @@
+[assembly:System.Runtime.CompilerServices.InternalsVisibleTo("Avalonia.Base.UnitTests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100c1bba1142285fe0419326fb25866ba62c47e6c2b5c1ab0c95b46413fad375471232cb81706932e1cef38781b9ebd39d5100401bacb651c6c5bbf59e571e81b3bc08d2a622004e08b1a6ece82a7e0b9857525c86d2b95fab4bc3dce148558d7f3ae61aa3a234086902aeface87d9dfdd32b9d2fe3c6dd4055b5ab4b104998bd87")]
+[assembly:System.Runtime.CompilerServices.InternalsVisibleTo("Avalonia.Controls.UnitTests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100c1bba1142285fe0419326fb25866ba62c47e6c2b5c1ab0c95b46413fad375471232cb81706932e1cef38781b9ebd39d5100401bacb651c6c5bbf59e571e81b3bc08d2a622004e08b1a6ece82a7e0b9857525c86d2b95fab4bc3dce148558d7f3ae61aa3a234086902aeface87d9dfdd32b9d2fe3c6dd4055b5ab4b104998bd87")]
+[assembly:System.Runtime.CompilerServices.InternalsVisibleTo("Avalonia.Benchmarks, PublicKey=0024000004800000940000000602000000240000525341310004000001000100c1bba1142285fe0419326fb25866ba62c47e6c2b5c1ab0c95b46413fad375471232cb81706932e1cef38781b9ebd39d5100401bacb651c6c5bbf59e571e81b3bc08d2a622004e08b1a6ece82a7e0b9857525c86d2b95fab4bc3dce148558d7f3ae61aa3a234086902aeface87d9dfdd32b9d2fe3c6dd4055b5ab4b104998bd87")]
+[assembly:System.Runtime.CompilerServices.InternalsVisibleTo("Avalonia.Markup.UnitTests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100c1bba1142285fe0419326fb25866ba62c47e6c2b5c1ab0c95b46413fad375471232cb81706932e1cef38781b9ebd39d5100401bacb651c6c5bbf59e571e81b3bc08d2a622004e08b1a6ece82a7e0b9857525c86d2b95fab4bc3dce148558d7f3ae61aa3a234086902aeface87d9dfdd32b9d2fe3c6dd4055b5ab4b104998bd87")]
+[assembly:System.Runtime.CompilerServices.InternalsVisibleTo("Avalonia.Markup.Xaml.UnitTests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100c1bba1142285fe0419326fb25866ba62c47e6c2b5c1ab0c95b46413fad375471232cb81706932e1cef38781b9ebd39d5100401bacb651c6c5bbf59e571e81b3bc08d2a622004e08b1a6ece82a7e0b9857525c86d2b95fab4bc3dce148558d7f3ae61aa3a234086902aeface87d9dfdd32b9d2fe3c6dd4055b5ab4b104998bd87")]
+[assembly:System.Runtime.CompilerServices.InternalsVisibleTo("Avalonia.LeakTests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100c1bba1142285fe0419326fb25866ba62c47e6c2b5c1ab0c95b46413fad375471232cb81706932e1cef38781b9ebd39d5100401bacb651c6c5bbf59e571e81b3bc08d2a622004e08b1a6ece82a7e0b9857525c86d2b95fab4bc3dce148558d7f3ae61aa3a234086902aeface87d9dfdd32b9d2fe3c6dd4055b5ab4b104998bd87")]
+[assembly:System.Runtime.CompilerServices.InternalsVisibleTo("Avalonia.Skia.UnitTests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100c1bba1142285fe0419326fb25866ba62c47e6c2b5c1ab0c95b46413fad375471232cb81706932e1cef38781b9ebd39d5100401bacb651c6c5bbf59e571e81b3bc08d2a622004e08b1a6ece82a7e0b9857525c86d2b95fab4bc3dce148558d7f3ae61aa3a234086902aeface87d9dfdd32b9d2fe3c6dd4055b5ab4b104998bd87")]
+[assembly:System.Runtime.CompilerServices.InternalsVisibleTo("Avalonia.Direct2D.UnitTests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100c1bba1142285fe0419326fb25866ba62c47e6c2b5c1ab0c95b46413fad375471232cb81706932e1cef38781b9ebd39d5100401bacb651c6c5bbf59e571e81b3bc08d2a622004e08b1a6ece82a7e0b9857525c86d2b95fab4bc3dce148558d7f3ae61aa3a234086902aeface87d9dfdd32b9d2fe3c6dd4055b5ab4b104998bd87")]
+
+
+
diff --git a/tests/Avalonia.UnitTests/MockGlobalClock.cs b/tests/Avalonia.UnitTests/MockGlobalClock.cs
index b53e5acc01..81aa1bbc97 100644
--- a/tests/Avalonia.UnitTests/MockGlobalClock.cs
+++ b/tests/Avalonia.UnitTests/MockGlobalClock.cs
@@ -3,7 +3,7 @@ using Avalonia.Animation;
 
 namespace Avalonia.UnitTests
 {
-    public class MockGlobalClock : ClockBase, IGlobalClock
+    internal class MockGlobalClock : ClockBase, IGlobalClock
     {
         public new void Pulse(TimeSpan systemTime) => base.Pulse(systemTime);
     }
diff --git a/tests/Avalonia.UnitTests/MockWindowingPlatform.cs b/tests/Avalonia.UnitTests/MockWindowingPlatform.cs
index ca71a97a6e..abd200ec7c 100644
--- a/tests/Avalonia.UnitTests/MockWindowingPlatform.cs
+++ b/tests/Avalonia.UnitTests/MockWindowingPlatform.cs
@@ -4,6 +4,7 @@ using Moq;
 using Avalonia.Platform;
 using Avalonia.Rendering;
 using Avalonia.Controls;
+using Avalonia.Rendering.Composition;
 
 namespace Avalonia.UnitTests
 {
@@ -24,18 +25,16 @@ namespace Avalonia.UnitTests
         public static Mock<IWindowImpl> CreateWindowMock(double initialWidth = 800, double initialHeight = 600)
         {
             var windowImpl = new Mock<IWindowImpl>();
-            var position = new PixelPoint();
             var clientSize = new Size(initialWidth,  initialHeight);
 
             windowImpl.SetupAllProperties();
-            windowImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>()))
-                .Returns(() => RendererMocks.CreateRenderer().Object);
+            var compositor = RendererMocks.CreateDummyCompositor();
+            windowImpl.Setup(x => x.Compositor).Returns(compositor);
             windowImpl.Setup(x => x.ClientSize).Returns(() => clientSize);
             windowImpl.Setup(x => x.MaxAutoSizeHint).Returns(s_screenSize);
             windowImpl.Setup(x => x.DesktopScaling).Returns(1);
             windowImpl.Setup(x => x.RenderScaling).Returns(1);
             windowImpl.Setup(x => x.Screen).Returns(CreateScreenMock().Object);
-            windowImpl.Setup(x => x.Position).Returns(() => position);
 
             windowImpl.Setup(r => r.TryGetFeature(It.IsAny<Type>())).Returns(null);
 
@@ -51,10 +50,16 @@ namespace Avalonia.UnitTests
 
             windowImpl.Setup(x => x.Move(It.IsAny<PixelPoint>())).Callback<PixelPoint>(x =>
             {
-                position = x;
+                windowImpl.Setup(x => x.Position).Returns(x);
                 windowImpl.Object.PositionChanged?.Invoke(x);
             });
 
+            windowImpl.Setup(x => x.PointToScreen(It.IsAny<Point>()))
+                .Returns<Point>((point) => PixelPoint.FromPoint(point, 1) + windowImpl.Object.Position);
+
+            windowImpl.Setup(x => x.PointToClient(It.IsAny<PixelPoint>()))
+                .Returns<PixelPoint>(point => (point - windowImpl.Object.Position).ToPoint(1));
+
             windowImpl.Setup(x => x.Resize(It.IsAny<Size>(), It.IsAny<WindowResizeReason>()))
                 .Callback<Size, WindowResizeReason>((x, y) =>
             {
@@ -73,9 +78,6 @@ namespace Avalonia.UnitTests
                 windowImpl.Object.Activated?.Invoke();
             });
 
-            windowImpl.Setup(x => x.PointToScreen(It.IsAny<Point>()))
-                .Returns((Point p) => PixelPoint.FromPoint(p, 1D) + position);
-
             return windowImpl;
         }
 
@@ -83,10 +85,12 @@ namespace Avalonia.UnitTests
         {
             var popupImpl = new Mock<IPopupImpl>();
             var clientSize = new Size();
+            var position = new PixelPoint();
 
             var positionerHelper = new ManagedPopupPositionerPopupImplHelper(parent, (pos, size, scale) =>
             {
                 clientSize = size.Constrain(s_screenSize);
+                position = pos;
                 popupImpl.Object.PositionChanged?.Invoke(pos);
                 popupImpl.Object.Resized?.Invoke(clientSize, WindowResizeReason.Unspecified);
             });
@@ -94,12 +98,21 @@ namespace Avalonia.UnitTests
             var positioner = new ManagedPopupPositioner(positionerHelper);
 
             popupImpl.SetupAllProperties();
-            popupImpl.Setup(x => x.CreateRenderer(It.IsAny<IRenderRoot>()))
-                .Returns(() => RendererMocks.CreateRenderer().Object);
+            var compositor = RendererMocks.CreateDummyCompositor();
+            popupImpl.Setup(x => x.Compositor).Returns(compositor);
             popupImpl.Setup(x => x.ClientSize).Returns(() => clientSize);
             popupImpl.Setup(x => x.MaxAutoSizeHint).Returns(s_screenSize);
             popupImpl.Setup(x => x.RenderScaling).Returns(1);
             popupImpl.Setup(x => x.PopupPositioner).Returns(positioner);
+            popupImpl.Setup(x => x.Position).Returns(()=>position);
+
+            popupImpl.Setup(x => x.PointToScreen(It.IsAny<Point>()))
+                .Returns<Point>((point) => PixelPoint.FromPoint(point, 1) + position);
+
+            popupImpl.Setup(x => x.PointToClient(It.IsAny<PixelPoint>()))
+                .Returns<PixelPoint>(point => (point - position).ToPoint(1));
+
+
 
             popupImpl.Setup(r => r.TryGetFeature(It.IsAny<Type>())).Returns(null);
             popupImpl.Setup(x => x.Dispose()).Callback(() =>
diff --git a/tests/Avalonia.UnitTests/NullRenderer.cs b/tests/Avalonia.UnitTests/NullRenderer.cs
index 1b59aa30eb..a001ec0d6e 100644
--- a/tests/Avalonia.UnitTests/NullRenderer.cs
+++ b/tests/Avalonia.UnitTests/NullRenderer.cs
@@ -12,7 +12,12 @@ public sealed class NullRenderer : IRenderer
 {
     public RendererDiagnostics Diagnostics { get; } = new();
 
-    public event EventHandler<SceneInvalidatedEventArgs>? SceneInvalidated;
+    event EventHandler<SceneInvalidatedEventArgs>? IRenderer.SceneInvalidated
+    {
+        add { }
+        remove { }
+    }
+
 
     public NullRenderer()
     {
diff --git a/tests/Avalonia.UnitTests/RendererMocks.cs b/tests/Avalonia.UnitTests/RendererMocks.cs
index d4808a7556..ba9bf31950 100644
--- a/tests/Avalonia.UnitTests/RendererMocks.cs
+++ b/tests/Avalonia.UnitTests/RendererMocks.cs
@@ -1,15 +1,34 @@
-using Avalonia.Rendering;
+using Avalonia.Media;
+using Avalonia.Platform;
+using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
+using Avalonia.Threading;
 using Moq;
 
 namespace Avalonia.UnitTests
 {
     public static class RendererMocks
     {
-        public static Mock<IRenderer> CreateRenderer()
+        internal static Mock<IRenderer> CreateRenderer()
         {
             var renderer = new Mock<IRenderer>();
             renderer.SetupGet(r => r.Diagnostics).Returns(new RendererDiagnostics());
             return renderer;
         }
+
+        public static Compositor CreateDummyCompositor() =>
+            new(new RenderLoop(new CompositorTestServices.ManualRenderTimer()), null, false,
+                new CompositionCommitScheduler(), true);
+
+        class CompositionCommitScheduler : ICompositorScheduler
+        {
+            public void CommitRequested(Compositor compositor)
+            {
+                if (AvaloniaLocator.Current.GetService<IPlatformRenderInterface>() == null)
+                    return;
+                
+                Dispatcher.UIThread.Post(() => compositor.Commit(), DispatcherPriority.AfterRender);
+            }
+        }
     }
 }
diff --git a/tests/Avalonia.UnitTests/ScopedTestBase.cs b/tests/Avalonia.UnitTests/ScopedTestBase.cs
new file mode 100644
index 0000000000..5104823c7b
--- /dev/null
+++ b/tests/Avalonia.UnitTests/ScopedTestBase.cs
@@ -0,0 +1,27 @@
+using System;
+using System.Threading;
+using Avalonia.Controls;
+using Avalonia.Threading;
+using Xunit;
+
+namespace Avalonia.UnitTests;
+
+[Collection("Scoped Not Parallel")]
+public class ScopedTestBase : IDisposable
+{
+    private readonly IDisposable _scope;
+
+    public ScopedTestBase()
+    {
+        AvaloniaLocator.Current = AvaloniaLocator.CurrentMutable = new AvaloniaLocator();
+        Dispatcher.ResetBeforeUnitTests();
+        Control.ResetLoadedQueueForUnitTests();
+        _scope = AvaloniaLocator.EnterScope();
+    }
+    
+    public virtual void Dispose()
+    {
+        Dispatcher.ResetForUnitTests();
+        _scope.Dispose();
+    }
+}
\ No newline at end of file
diff --git a/tests/Avalonia.UnitTests/TestExtensions.cs b/tests/Avalonia.UnitTests/TestExtensions.cs
deleted file mode 100644
index 21a67a8800..0000000000
--- a/tests/Avalonia.UnitTests/TestExtensions.cs
+++ /dev/null
@@ -1,13 +0,0 @@
-using System;
-using Avalonia.Controls.Presenters;
-using Avalonia.Controls.Primitives;
-using Avalonia.Layout;
-using Avalonia.Styling;
-
-namespace Avalonia.UnitTests
-{
-    public static class TestExtensions
-    {
-        public static void ApplyTemplate(this IContentPresenter presenter) => ((Layoutable)presenter).ApplyTemplate();
-    }
-}
diff --git a/tests/Avalonia.UnitTests/TestRoot.cs b/tests/Avalonia.UnitTests/TestRoot.cs
index 80f0cf5406..569e5d114c 100644
--- a/tests/Avalonia.UnitTests/TestRoot.cs
+++ b/tests/Avalonia.UnitTests/TestRoot.cs
@@ -1,3 +1,5 @@
+using System;
+using System.Collections.Generic;
 using Avalonia.Controls;
 using Avalonia.Input;
 using Avalonia.Layout;
@@ -17,11 +19,19 @@ namespace Avalonia.UnitTests
         public TestRoot()
         {
             Renderer = RendererMocks.CreateRenderer().Object;
+            HitTester = new NullHitTester();
             LayoutManager = new LayoutManager(this);
             IsVisible = true;
             KeyboardNavigation.SetTabNavigation(this, KeyboardNavigationMode.Cycle);
         }
 
+        class NullHitTester : IHitTester
+        {
+            public IEnumerable<Visual> HitTest(Point p, Visual root, Func<Visual, bool> filter) => Array.Empty<Visual>();
+
+            public Visual HitTestFirst(Point p, Visual root, Func<Visual, bool> filter) => null;
+        }
+
         public TestRoot(Control child)
             : this(false, child)
         {
@@ -45,11 +55,15 @@ namespace Avalonia.UnitTests
 
         public double LayoutScaling { get; set; } = 1;
 
-        public ILayoutManager LayoutManager { get; set; }
+        internal ILayoutManager LayoutManager { get; set; }
+        ILayoutManager ILayoutRoot.LayoutManager => LayoutManager;
 
         public double RenderScaling => 1;
 
-        public IRenderer Renderer { get; set; }
+        internal IRenderer Renderer { get; set; }
+        internal IHitTester HitTester { get; set; }
+        IRenderer IRenderRoot.Renderer => Renderer;
+        IHitTester IRenderRoot.HitTester => HitTester;
 
         public IKeyboardNavigationHandler KeyboardNavigationHandler => null;
         public IFocusManager FocusManager => AvaloniaLocator.Current.GetService<IFocusManager>();
diff --git a/tests/Avalonia.UnitTests/TestServices.cs b/tests/Avalonia.UnitTests/TestServices.cs
index f226a7ef55..95a1436ac9 100644
--- a/tests/Avalonia.UnitTests/TestServices.cs
+++ b/tests/Avalonia.UnitTests/TestServices.cs
@@ -65,7 +65,6 @@ namespace Avalonia.UnitTests
         public TestServices(
             IAssetLoader assetLoader = null,
             IFocusManager focusManager = null,
-            IGlobalClock globalClock = null,
             IInputManager inputManager = null,
             Func<IKeyboardDevice> keyboardDevice = null,
             IKeyboardNavigationHandler keyboardNavigation = null,
@@ -83,7 +82,6 @@ namespace Avalonia.UnitTests
         {
             AssetLoader = assetLoader;
             FocusManager = focusManager;
-            GlobalClock = globalClock;
             InputManager = inputManager;
             KeyboardDevice = keyboardDevice;
             KeyboardNavigation = keyboardNavigation;
@@ -99,10 +97,35 @@ namespace Avalonia.UnitTests
             WindowingPlatform = windowingPlatform;
         }
 
+        internal TestServices(
+            IGlobalClock globalClock,
+            IAssetLoader assetLoader = null,
+            IFocusManager focusManager = null,
+            IInputManager inputManager = null,
+            Func<IKeyboardDevice> keyboardDevice = null,
+            IKeyboardNavigationHandler keyboardNavigation = null,
+            Func<IMouseDevice> mouseDevice = null,
+            IRuntimePlatform platform = null,
+            IPlatformRenderInterface renderInterface = null,
+            IRenderTimer renderLoop = null,
+            ICursorFactory standardCursorFactory = null,
+            Func<IStyle> theme = null,
+            IDispatcherImpl dispatcherImpl = null,
+            IFontManagerImpl fontManagerImpl = null,
+            ITextShaperImpl textShaperImpl = null,
+            IWindowImpl windowImpl = null,
+            IWindowingPlatform windowingPlatform = null) : this(assetLoader, focusManager, inputManager, keyboardDevice,
+            keyboardNavigation,
+            mouseDevice, platform, renderInterface, renderLoop, standardCursorFactory, theme,
+            dispatcherImpl, fontManagerImpl, textShaperImpl, windowImpl, windowingPlatform)
+        {
+            GlobalClock = globalClock;
+        }
+
         public IAssetLoader AssetLoader { get; }
         public IInputManager InputManager { get; }
         public IFocusManager FocusManager { get; }
-        public IGlobalClock GlobalClock { get; }
+        internal IGlobalClock GlobalClock { get; set; }
         public Func<IKeyboardDevice> KeyboardDevice { get; }
         public IKeyboardNavigationHandler KeyboardNavigation { get; }
         public Func<IMouseDevice> MouseDevice { get; }
@@ -116,10 +139,9 @@ namespace Avalonia.UnitTests
         public IWindowImpl WindowImpl { get; }
         public IWindowingPlatform WindowingPlatform { get; }
 
-        public TestServices With(
+        internal TestServices With(
             IAssetLoader assetLoader = null,
             IFocusManager focusManager = null,
-            IGlobalClock globalClock = null,
             IInputManager inputManager = null,
             Func<IKeyboardDevice> keyboardDevice = null,
             IKeyboardNavigationHandler keyboardNavigation = null,
@@ -134,12 +156,13 @@ namespace Avalonia.UnitTests
             IFontManagerImpl fontManagerImpl = null,
             ITextShaperImpl textShaperImpl = null,
             IWindowImpl windowImpl = null,
-            IWindowingPlatform windowingPlatform = null)
+            IWindowingPlatform windowingPlatform = null,
+            IGlobalClock globalClock = null)
         {
             return new TestServices(
+                globalClock ?? GlobalClock,
                 assetLoader: assetLoader ?? AssetLoader,
                 focusManager: focusManager ?? FocusManager,
-                globalClock: globalClock ?? GlobalClock,
                 inputManager: inputManager ?? InputManager,
                 keyboardDevice: keyboardDevice ?? KeyboardDevice,
                 keyboardNavigation: keyboardNavigation ?? KeyboardNavigation,