diff --git a/samples/ControlCatalog/App.xaml b/samples/ControlCatalog/App.xaml
index c7a75f5a70..1c8c38d3e5 100644
--- a/samples/ControlCatalog/App.xaml
+++ b/samples/ControlCatalog/App.xaml
@@ -4,14 +4,14 @@
   <Application.Styles>        
     <StyleInclude Source="avares://Avalonia.Controls.DataGrid/Themes/Default.xaml"/>
     <Style Selector="TextBlock.h1">
-      <Setter Property="FontSize" Value="{DynamicResource FontSizeLarge}"/>
-      <Setter Property="FontWeight" Value="Medium"/>
+      <Setter Property="FontSize" Value="16" />
+      <Setter Property="FontWeight" Value="Medium" />
     </Style>
     <Style Selector="TextBlock.h2">
-      <Setter Property="FontSize" Value="{DynamicResource FontSizeNormal}"/>
+      <Setter Property="FontSize" Value="14" />
     </Style>
     <Style Selector="TextBlock.h3">
-      <Setter Property="FontSize" Value="{DynamicResource FontSizeSmall}"/>
+      <Setter Property="FontSize" Value="10" />
     </Style>
     <StyleInclude Source="/SideBar.xaml"/>
   </Application.Styles>
diff --git a/samples/ControlCatalog/App.xaml.cs b/samples/ControlCatalog/App.xaml.cs
index 3f1ec289d1..b0fbcc76d2 100644
--- a/samples/ControlCatalog/App.xaml.cs
+++ b/samples/ControlCatalog/App.xaml.cs
@@ -67,9 +67,9 @@ namespace ControlCatalog
 
         public override void Initialize()
         {
-            AvaloniaXamlLoader.Load(this);
-
             Styles.Insert(0, FluentDark);
+
+            AvaloniaXamlLoader.Load(this);
         }
 
         public override void OnFrameworkInitializationCompleted()
diff --git a/samples/ControlCatalog/MainView.xaml b/samples/ControlCatalog/MainView.xaml
index af95e3c356..efc90357ed 100644
--- a/samples/ControlCatalog/MainView.xaml
+++ b/samples/ControlCatalog/MainView.xaml
@@ -1,9 +1,7 @@
 <UserControl xmlns="https://github.com/avaloniaui"
         xmlns:pages="clr-namespace:ControlCatalog.Pages"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        x:Class="ControlCatalog.MainView"
-        Foreground="{DynamicResource ThemeForegroundBrush}"
-        FontSize="{DynamicResource FontSizeNormal}">
+        x:Class="ControlCatalog.MainView">
   <Grid>
     <Grid.Styles>
         <Style Selector="TextBlock.h2">
diff --git a/samples/ControlCatalog/MainWindow.xaml.cs b/samples/ControlCatalog/MainWindow.xaml.cs
index d97325ef8d..a316321cd1 100644
--- a/samples/ControlCatalog/MainWindow.xaml.cs
+++ b/samples/ControlCatalog/MainWindow.xaml.cs
@@ -63,8 +63,18 @@ namespace ControlCatalog
             // TODO: iOS does not support dynamically loading assemblies
             // so we must refer to this resource DLL statically. For
             // now I am doing that here. But we need a better solution!!
-            var theme = new Avalonia.Themes.Default.DefaultTheme();
-            theme.TryGetResource("Button", out _);
+            // Note, theme swiching probably will not work in runtime for iOS.
+            if (Application.Current.Styles.Contains(App.FluentDark)
+                || Application.Current.Styles.Contains(App.FluentLight))
+            {
+                var theme = new Avalonia.Themes.Fluent.FluentTheme();
+                theme.TryGetResource("Button", out _);
+            }
+            else
+            {
+                var theme = new Avalonia.Themes.Default.DefaultTheme();
+                theme.TryGetResource("Button", out _);
+            }
             AvaloniaXamlLoader.Load(this);
         }
     }
diff --git a/samples/ControlCatalog/Pages/ButtonPage.xaml b/samples/ControlCatalog/Pages/ButtonPage.xaml
index a4427c70c5..be114bbbc9 100644
--- a/samples/ControlCatalog/Pages/ButtonPage.xaml
+++ b/samples/ControlCatalog/Pages/ButtonPage.xaml
@@ -20,6 +20,10 @@
               <Style.Resources>
                 <SolidColorBrush x:Key="ThemeBorderMidBrush">Red</SolidColorBrush>
                 <SolidColorBrush x:Key="ThemeControlHighBrush">DarkRed</SolidColorBrush>
+                <SolidColorBrush x:Key="ButtonBorderBrush">Red</SolidColorBrush>
+                <SolidColorBrush x:Key="ButtonBackground">DarkRed</SolidColorBrush>
+                <SolidColorBrush x:Key="ButtonBackgroundPointerOver">Red</SolidColorBrush>
+                <SolidColorBrush x:Key="ButtonBackgroundPressed">OrangeRed</SolidColorBrush>
               </Style.Resources>
             </Style>
           </Button.Styles>          
diff --git a/samples/ControlCatalog/Pages/ItemsRepeaterPage.xaml b/samples/ControlCatalog/Pages/ItemsRepeaterPage.xaml
index 304782dbf9..392ccb57c3 100644
--- a/samples/ControlCatalog/Pages/ItemsRepeaterPage.xaml
+++ b/samples/ControlCatalog/Pages/ItemsRepeaterPage.xaml
@@ -43,7 +43,7 @@
       <Button x:Name="scrollToLast">Scroll to Last</Button>
       <Button x:Name="scrollToRandom">Scroll to Random</Button>
     </StackPanel>
-    <Border BorderThickness="1" BorderBrush="{DynamicResource ThemeBorderMidBrush}" Margin="0 0 0 16">
+    <Border BorderThickness="1" BorderBrush="{DynamicResource SystemControlHighlightBaseMediumLowBrush}" Margin="0 0 0 16">
       <ScrollViewer Name="scroller"
                     HorizontalScrollBarVisibility="Auto"
                     VerticalScrollBarVisibility="Auto">
diff --git a/samples/ControlCatalog/Pages/ScreenPage.cs b/samples/ControlCatalog/Pages/ScreenPage.cs
index d775eb9635..c39f414b44 100644
--- a/samples/ControlCatalog/Pages/ScreenPage.cs
+++ b/samples/ControlCatalog/Pages/ScreenPage.cs
@@ -29,7 +29,8 @@ namespace ControlCatalog.Pages
             var screens = w.Screens.All;
             var scaling = ((IRenderRoot)w).RenderScaling;
 
-            Pen p = new Pen(Brushes.Black);
+            var drawBrush = Brushes.Green;
+            Pen p = new Pen(drawBrush);
             if (screens != null)
                 foreach (Screen screen in screens)
                 {
@@ -53,19 +54,19 @@ namespace ControlCatalog.Pages
                     };
 
                     text.Text = $"Bounds: {screen.Bounds.Width}:{screen.Bounds.Height}";
-                    context.DrawText(Brushes.Black, boundsRect.Position.WithY(boundsRect.Size.Height), text);
+                    context.DrawText(drawBrush, boundsRect.Position.WithY(boundsRect.Size.Height), text);
                     
                     text.Text = $"WorkArea: {screen.WorkingArea.Width}:{screen.WorkingArea.Height}";
-                    context.DrawText(Brushes.Black, boundsRect.Position.WithY(boundsRect.Size.Height + 20), text);
+                    context.DrawText(drawBrush, boundsRect.Position.WithY(boundsRect.Size.Height + 20), text);
 
                     text.Text = $"Scaling: {screen.PixelDensity * 100}%";
-                    context.DrawText(Brushes.Black, boundsRect.Position.WithY(boundsRect.Size.Height + 40), text);
+                    context.DrawText(drawBrush, boundsRect.Position.WithY(boundsRect.Size.Height + 40), text);
                     
                     text.Text = $"Primary: {screen.Primary}";
-                    context.DrawText(Brushes.Black, boundsRect.Position.WithY(boundsRect.Size.Height + 60), text);
+                    context.DrawText(drawBrush, boundsRect.Position.WithY(boundsRect.Size.Height + 60), text);
                     
                     text.Text = $"Current: {screen.Equals(w.Screens.ScreenFromBounds(new PixelRect(w.Position, PixelSize.FromSize(w.Bounds.Size, scaling))))}";
-                    context.DrawText(Brushes.Black, boundsRect.Position.WithY(boundsRect.Size.Height + 80), text);
+                    context.DrawText(drawBrush, boundsRect.Position.WithY(boundsRect.Size.Height + 80), text);
                 }
 
             context.DrawRectangle(p, new Rect(w.Position.X / 10f + Math.Abs(_leftMost), w.Position.Y / 10, w.Bounds.Width / 10, w.Bounds.Height / 10));
diff --git a/samples/ControlCatalog/Pages/TextBlockPage.xaml b/samples/ControlCatalog/Pages/TextBlockPage.xaml
index 4b8edcf98c..4a1c196917 100644
--- a/samples/ControlCatalog/Pages/TextBlockPage.xaml
+++ b/samples/ControlCatalog/Pages/TextBlockPage.xaml
@@ -12,7 +12,7 @@
       <StackPanel.Styles>
         <Style Selector="Border">
           <Setter Property="BorderThickness" Value="1"/>
-          <Setter Property="BorderBrush" Value="{DynamicResource ThemeBorderMidBrush}"/>
+          <Setter Property="BorderBrush" Value="{DynamicResource SystemControlHighlightBaseMediumLowBrush}"/>
           <Setter Property="Padding" Value="2"/>
         </Style>
       </StackPanel.Styles>
@@ -49,7 +49,7 @@
       <StackPanel.Styles>
         <Style Selector="Border">
           <Setter Property="BorderThickness" Value="1"/>
-          <Setter Property="BorderBrush" Value="{DynamicResource ThemeBorderMidBrush}"/>
+          <Setter Property="BorderBrush" Value="{DynamicResource SystemControlHighlightBaseMediumLowBrush}"/>
           <Setter Property="Padding" Value="2"/>
         </Style>
       </StackPanel.Styles>
diff --git a/src/Avalonia.Controls/DateTimePickers/DatePickerPresenter.cs b/src/Avalonia.Controls/DateTimePickers/DatePickerPresenter.cs
index 31527ccb16..eec4615736 100644
--- a/src/Avalonia.Controls/DateTimePickers/DatePickerPresenter.cs
+++ b/src/Avalonia.Controls/DateTimePickers/DatePickerPresenter.cs
@@ -356,10 +356,17 @@ namespace Avalonia.Controls
             }
 
             if (MonthVisible)
+            {
                 _monthSelector.SelectedValue = dt.Month;
-
+                _monthSelector.FormatDate = dt.Date;
+            }
+               
             if (YearVisible)
+            {
                 _yearSelector.SelectedValue = dt.Year;
+                _yearSelector.FormatDate = dt.Date;
+            }
+                
             _suppressUpdateSelection = false;
 
             SetInitialFocus();
diff --git a/src/Avalonia.Controls/Repeater/ItemsSourceView.cs b/src/Avalonia.Controls/Repeater/ItemsSourceView.cs
index ecf8abc13f..def9301e2d 100644
--- a/src/Avalonia.Controls/Repeater/ItemsSourceView.cs
+++ b/src/Avalonia.Controls/Repeater/ItemsSourceView.cs
@@ -25,7 +25,6 @@ namespace Avalonia.Controls
     {
         private readonly IList _inner;
         private INotifyCollectionChanged _notifyCollectionChanged;
-        private int _cachedSize = -1;
 
         /// <summary>
         /// Initializes a new instance of the ItemsSourceView class for the specified data source.
@@ -54,18 +53,7 @@ namespace Avalonia.Controls
         /// <summary>
         /// Gets the number of items in the collection.
         /// </summary>
-        public int Count
-        {
-            get
-            {
-                if (_cachedSize == -1)
-                {
-                    _cachedSize = _inner.Count;
-                }
-
-                return _cachedSize;
-            }
-        }
+        public int Count => _inner.Count;
 
         /// <summary>
         /// Gets a value that indicates whether the items source can provide a unique key for each item.
@@ -126,7 +114,6 @@ namespace Avalonia.Controls
 
         protected void OnItemsSourceChanged(NotifyCollectionChangedEventArgs args)
         {
-            _cachedSize = _inner.Count;
             CollectionChanged?.Invoke(this, args);
         }
 
diff --git a/src/Avalonia.Dialogs/ManagedFileChooser.xaml b/src/Avalonia.Dialogs/ManagedFileChooser.xaml
index 8a0451f982..227cc1afc0 100644
--- a/src/Avalonia.Dialogs/ManagedFileChooser.xaml
+++ b/src/Avalonia.Dialogs/ManagedFileChooser.xaml
@@ -66,7 +66,7 @@
             </StackPanel>
         </DockPanel>
 
-        <DropDown DockPanel.Dock="Bottom" 
+        <ComboBox DockPanel.Dock="Bottom" 
                   IsVisible="{Binding ShowFilters}" 
                   Items="{Binding Filters}"
                   SelectedItem="{Binding SelectedFilter}"
@@ -76,7 +76,7 @@
 
         <ListBox Margin="0 0 5 5" BorderBrush="Transparent" x:Name="QuickLinks" Items="{Binding QuickLinks}"
                  SelectedIndex="{Binding QuickLinksSelectedIndex}"
-                 DockPanel.Dock="Left" Background="{DynamicResource ThemeControlMidBrush}" Focusable="False">
+                 DockPanel.Dock="Left" Focusable="False">
             <ListBox.ItemTemplate>
                 <DataTemplate>
                     <StackPanel Spacing="4" Orientation="Horizontal" Background="Transparent">
diff --git a/src/Avalonia.Themes.Default/Accents/BaseDark.xaml b/src/Avalonia.Themes.Default/Accents/BaseDark.xaml
index ffe3e92202..44dfb9ea48 100644
--- a/src/Avalonia.Themes.Default/Accents/BaseDark.xaml
+++ b/src/Avalonia.Themes.Default/Accents/BaseDark.xaml
@@ -58,6 +58,11 @@
         <SolidColorBrush x:Key="NotificationCardWarningBackgroundBrush" Color="#FDB328" Opacity="0.75"/>
         <SolidColorBrush x:Key="NotificationCardErrorBackgroundBrush" Color="#BD202C" Opacity="0.75"/>
 
+        <SolidColorBrush x:Key="DatePickerFlyoutPresenterHighlightFill" Color="{DynamicResource ThemeAccentColor}" Opacity="0.4" />
+        <SolidColorBrush x:Key="TimePickerFlyoutPresenterHighlightFill" Color="{DynamicResource ThemeAccentColor}" Opacity="0.4" />
+
+        <SolidColorBrush x:Key="ThemeControlTransparentBrush" Color="Transparent" />
+      
         <Thickness x:Key="ThemeBorderThickness">1,1,1,1</Thickness>
         <sys:Double x:Key="ThemeDisabledOpacity">0.5</sys:Double>
 
diff --git a/src/Avalonia.Themes.Default/Accents/BaseLight.xaml b/src/Avalonia.Themes.Default/Accents/BaseLight.xaml
index c0e5f47eed..9ed3207235 100644
--- a/src/Avalonia.Themes.Default/Accents/BaseLight.xaml
+++ b/src/Avalonia.Themes.Default/Accents/BaseLight.xaml
@@ -61,6 +61,11 @@
         <SolidColorBrush x:Key="NotificationCardWarningBackgroundBrush" Color="#FDB328" Opacity="0.75"/>
         <SolidColorBrush x:Key="NotificationCardErrorBackgroundBrush" Color="#BD202C" Opacity="0.75"/>
 
+        <SolidColorBrush x:Key="DatePickerFlyoutPresenterHighlightFill" Color="{DynamicResource ThemeAccentColor}" Opacity="0.4" />
+        <SolidColorBrush x:Key="TimePickerFlyoutPresenterHighlightFill" Color="{DynamicResource ThemeAccentColor}" Opacity="0.4" />
+      
+        <SolidColorBrush x:Key="ThemeControlTransparentBrush" Color="Transparent" />
+
         <Thickness x:Key="ThemeBorderThickness">1</Thickness>
         <sys:Double x:Key="ThemeDisabledOpacity">0.5</sys:Double>
 
diff --git a/src/Avalonia.Themes.Default/DatePicker.xaml b/src/Avalonia.Themes.Default/DatePicker.xaml
new file mode 100644
index 0000000000..da878c88e2
--- /dev/null
+++ b/src/Avalonia.Themes.Default/DatePicker.xaml
@@ -0,0 +1,334 @@
+<!--
+// (c) Copyright Microsoft Corporation.
+// This source is subject to the Microsoft Public License (Ms-PL).
+// Please see http://go.microsoft.com/fwlink/?LinkID=131993 for details.
+// All other rights reserved.
+-->
+
+<Styles xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:sys="clr-namespace:System;assembly=netstandard">
+  <Styles.Resources>
+    <Thickness x:Key="DatePickerTopHeaderMargin">0,0,0,4</Thickness>
+    <x:Double x:Key="DatePickerFlyoutPresenterHighlightHeight">40</x:Double>
+    <x:Double x:Key="DatePickerFlyoutPresenterItemHeight">40</x:Double>
+    <x:Double x:Key="DatePickerFlyoutPresenterAcceptDismissHostGridHeight">41</x:Double>
+    <x:Double x:Key="DatePickerThemeMinWidth">296</x:Double>
+    <x:Double x:Key="DatePickerThemeMaxWidth">456</x:Double>
+    <Thickness x:Key="DatePickerFlyoutPresenterItemPadding">0,3,0,6</Thickness>
+    <Thickness x:Key="DatePickerFlyoutPresenterMonthPadding">9,3,0,6</Thickness>
+    <Thickness x:Key="DatePickerHostPadding">0,3,0,6</Thickness>
+    <Thickness x:Key="DatePickerHostMonthPadding">9,3,0,6</Thickness>
+    <x:Double x:Key="DatePickerSpacerThemeWidth">1</x:Double>
+  </Styles.Resources>
+
+  <!-- Styles for the items displayed in the selectors -->
+  <Style Selector="ListBoxItem.DateTimePickerItem">
+    <Setter Property="Padding" Value="{DynamicResource DatePickerFlyoutPresenterItemPadding}"/>
+    <Setter Property="VerticalContentAlignment" Value="Center" />
+    <Setter Property="HorizontalContentAlignment" Value="Center" />
+  </Style>
+  <Style Selector="ListBoxItem.DateTimePickerItem:selected">
+    <Setter Property="IsHitTestVisible" Value="False"/>
+  </Style>
+  <Style Selector="ListBoxItem.DateTimePickerItem:selected /template/ Rectangle#PressedBackground">
+    <Setter Property="Fill" Value="Transparent"/>
+  </Style>
+  <Style Selector="ListBoxItem.DateTimePickerItem:selected /template/ ContentPresenter">
+    <Setter Property="Background" Value="Transparent" />
+    <Setter Property="TextBlock.Foreground" Value="{DynamicResource ThemeForegroundBrush}"/>
+  </Style>
+  <Style Selector="ListBoxItem.DateTimePickerItem.MonthItem">
+    <Setter Property="Padding" Value="{DynamicResource DatePickerFlyoutPresenterMonthPadding}"/>
+    <Setter Property="VerticalContentAlignment" Value="Center" />
+    <Setter Property="HorizontalContentAlignment" Value="Left" />
+  </Style>
+
+
+  <!-- This is used for both the accept/dismiss & repeatbuttons in the presenter-->
+  <Style Selector=":is(Button).DateTimeFlyoutButtonStyle">
+    <Setter Property="Background" Value="{DynamicResource ThemeControlTransparentBrush}" />  
+    <Setter Property="HorizontalContentAlignment" Value="Center"/>
+    <Setter Property="VerticalContentAlignment" Value="Center"/>
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Border Background="{TemplateBinding Background}">
+          <ContentPresenter x:Name="ContentPresenter"
+                  Background="{TemplateBinding Background}"
+                  BorderBrush="{DynamicResource ThemeControlTransparentBrush}"
+                  BorderThickness="{DynamicResource DateTimeFlyoutButtonBorderThickness}"
+                  Content="{TemplateBinding Content}"
+                  TextBlock.Foreground="{DynamicResource ThemeForegroundBrush}"
+                  ContentTemplate="{TemplateBinding ContentTemplate}"
+                  Padding="{TemplateBinding Padding}"
+                  HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
+                  VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"/>
+        </Border>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+
+  <Style Selector=":is(Button).DateTimeFlyoutButtonStyle:pointerover /template/ ContentPresenter">
+    <Setter Property="Background" Value="{DynamicResource ThemeControlHighlightLowBrush}"/>
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeControlTransparentBrush}"/>
+    <Setter Property="TextBlock.Foreground" Value="{DynamicResource ThemeForegroundBrush}"/>
+  </Style>
+
+  <Style Selector=":is(Button).DateTimeFlyoutButtonStyle:pressed /template/ ContentPresenter">
+    <Setter Property="Background" Value="{DynamicResource ThemeControlHighlightMidBrush}"/>
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeControlTransparentBrush}"/>
+    <Setter Property="TextBlock.Foreground" Value="{DynamicResource ThemeForegroundBrush}"/>
+  </Style>
+
+
+  <Style Selector="RepeatButton.UpButton">
+    <Setter Property="VerticalAlignment" Value="Top"/>
+    <Setter Property="Height" Value="22" />
+    <Setter Property="HorizontalAlignment" Value="Stretch" />
+    <Setter Property="Focusable" Value="False" />
+    <Setter Property="Background" Value="{DynamicResource ThemeControlHighlightLowBrush}" />
+    <Setter Property="Content">
+      <Template>
+        <Viewbox Height="10" Width="10" HorizontalAlignment="Center" VerticalAlignment="Center">
+          <Path Stroke="{Binding $parent[RepeatButton].Foreground}" StrokeThickness="1" Data="M 0,9 L 9,0 L 18,9"/>
+        </Viewbox>
+      </Template>
+    </Setter>
+  </Style>
+  <Style Selector="RepeatButton.DownButton">
+    <Setter Property="VerticalAlignment" Value="Bottom"/>
+    <Setter Property="Height" Value="22" />
+    <Setter Property="HorizontalAlignment" Value="Stretch" />
+    <Setter Property="Focusable" Value="False" />
+    <Setter Property="Background" Value="{DynamicResource ThemeControlHighlightLowBrush}" />
+    <Setter Property="Content">
+      <Template>
+        <Viewbox Height="10" Width="10" HorizontalAlignment="Center" VerticalAlignment="Center">
+          <Path Stroke="{Binding $parent[RepeatButton].Foreground}" StrokeThickness="1" Data="M 0,0 L 9,9 L 18,0"/>
+        </Viewbox>
+      </Template>
+    </Setter>
+  </Style>
+
+  <Style Selector="DatePicker">    
+    <Setter Property="FontSize" Value="{DynamicResource FontSizeNormal}" />
+    <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundBrush}" />
+    <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}"/>
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeControlHighlightMidBrush}"/>
+    <Setter Property="BorderThickness" Value="1"/>
+    <Setter Property="HorizontalAlignment" Value="Left" />
+    <Setter Property="VerticalAlignment" Value="Center" />
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Grid Name="LayoutRoot" Margin="{TemplateBinding Padding}" RowDefinitions="Auto,*">
+          <ContentPresenter Name="HeaderContentPresenter" Grid.Row="0"
+                            Content="{TemplateBinding Header}"
+                            ContentTemplate="{TemplateBinding HeaderTemplate}"
+                            Margin="{DynamicResource DatePickerTopHeaderMargin}"
+                            MaxWidth="{DynamicResource DatePickerThemeMaxWidth}"
+                            HorizontalAlignment="Stretch"
+                            VerticalAlignment="Top"/>
+
+          <Button Name="FlyoutButton" Grid.Row="1"
+                  Foreground="{TemplateBinding Foreground}"
+                  Background="{TemplateBinding Background}"
+                  BorderBrush="{TemplateBinding BorderBrush}"
+                  BorderThickness="{TemplateBinding BorderThickness}"
+                  IsEnabled="{TemplateBinding IsEnabled}"
+                  MinWidth="{DynamicResource DatePickerThemeMinWidth}"
+                  MaxWidth="{DynamicResource DatePickerThemeMaxWidth}"
+                  HorizontalAlignment="Stretch"
+                  VerticalAlignment="Stretch"
+                  HorizontalContentAlignment="Stretch"
+                  VerticalContentAlignment="Stretch"
+                  TemplatedControl.IsTemplateFocusTarget="True">
+            <Button.Template>
+              <ControlTemplate>
+                <ContentPresenter Name="ContentPresenter"
+                                  BorderBrush="{TemplateBinding BorderBrush}"
+                                  Background="{TemplateBinding Background}"
+                                  BorderThickness="{TemplateBinding BorderThickness}"
+                                  Content="{TemplateBinding Content}"
+                                  TextBlock.Foreground="{TemplateBinding Foreground}"
+                                  HorizontalContentAlignment="Stretch"
+                                  VerticalContentAlignment="Stretch"/>
+              </ControlTemplate>
+            </Button.Template>
+            <Grid Name="ButtonContentGrid" ColumnDefinitions="78*,Auto,132*,Auto,78*">
+              <TextBlock Name="DayText" Text="day" HorizontalAlignment="Center"
+                         Padding="{DynamicResource DatePickerHostPadding}"
+                         FontFamily="{TemplateBinding FontFamily}"
+                         FontWeight="{TemplateBinding FontWeight}"
+                         FontSize="{TemplateBinding FontSize}"/>
+              <TextBlock Name="MonthText" Text="month" TextAlignment="Left"
+                         Padding="{DynamicResource DatePickerHostMonthPadding}"
+                         FontFamily="{TemplateBinding FontFamily}"
+                         FontWeight="{TemplateBinding FontWeight}"
+                         FontSize="{TemplateBinding FontSize}"/>
+              <TextBlock Name="YearText" Text="year" HorizontalAlignment="Center"
+                         Padding="{DynamicResource DatePickerHostPadding}"
+                         FontFamily="{TemplateBinding FontFamily}"
+                         FontWeight="{TemplateBinding FontWeight}"
+                         FontSize="{TemplateBinding FontSize}"/>
+              <Rectangle x:Name="FirstSpacer"
+                    Fill="{DynamicResource ThemeControlMidHighBrush}"
+                    HorizontalAlignment="Center"
+                    Width="1"
+                    Grid.Column="1" />
+              <Rectangle x:Name="SecondSpacer"
+                    Fill="{DynamicResource ThemeControlMidHighBrush}"
+                    HorizontalAlignment="Center"
+                    Width="1"
+                    Grid.Column="3" />
+            </Grid>
+          </Button>
+
+          <Popup Name="Popup" WindowManagerAddShadowHint="False"
+                 StaysOpen="False" PlacementTarget="{TemplateBinding}"
+                 PlacementMode="Bottom">
+            <DatePickerPresenter Name="PickerPresenter" />
+          </Popup>
+
+        </Grid>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+  <Style Selector="DatePicker /template/ ContentPresenter#HeaderContentPresenter">
+    <Setter Property="TextBlock.Foreground" Value="{DynamicResource ThemeForegroundBrush}"/>
+  </Style>
+  <Style Selector="DatePicker:disabled /template/ Rectangle">
+    <!--<Setter Property="Fill" Value="{DynamicResource DatePickerSpacerFillDisabled}"/>-->
+    <Setter Property="Opacity" Value="{DynamicResource ThemeDisabledOpacity}" />
+  </Style>
+
+  <Style Selector="DatePicker /template/ Button#FlyoutButton:pointerover /template/ ContentPresenter">
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeControlHighBrush}"/>
+    <!--<Setter Property="Background" Value="{DynamicResource DatePickerButtonBackgroundPointerOver}"/>-->
+    <Setter Property="TextBlock.Foreground" Value="{DynamicResource ThemeForegroundBrush}"/>
+  </Style>
+
+  <Style Selector="DatePicker /template/ Button#FlyoutButton:pressed /template/ ContentPresenter">
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeControlLowBrush}"/>
+    <Setter Property="Background">
+      <SolidColorBrush Color="{DynamicResource ThemeControlMidHighColor}" Opacity="0.6" />
+    </Setter>
+    <Setter Property="TextBlock.Foreground" Value="{DynamicResource ThemeForegroundBrush}"/>
+  </Style>
+
+  <Style Selector="DatePicker /template/ Button#FlyoutButton:disabled /template/ ContentPresenter">
+    <!--<Setter Property="BorderBrush" Value="{DynamicResource DatePickerButtonBorderBrushDisabled}"/>
+    <Setter Property="Background" Value="{DynamicResource DatePickerButtonBackgroundDisabled}"/>
+    <Setter Property="TextBlock.Foreground" Value="{DynamicResource DatePickerButtonForegroundDisabled}"/>-->
+    <Setter Property="Opacity" Value="{DynamicResource ThemeDisabledOpacity}" />
+  </Style>
+
+  <!-- Changes foreground for watermark text when SelectedDate is null-->
+  <Style Selector="DatePicker:hasnodate /template/ Button#FlyoutButton TextBlock">
+    <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundLowBrush}"/>
+  </Style>
+
+  <!--WinUI: DatePickerFlyoutPresenter-->
+  <Style Selector="DatePickerPresenter">
+    <Setter Property="Width" Value="296" />
+    <Setter Property="MinWidth" Value="296" />
+    <Setter Property="MaxHeight" Value="398" />    
+    <Setter Property="FontWeight" Value="Normal" />
+    <Setter Property="FontSize" Value="{DynamicResource FontSizeNormal}" />
+    <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}" />
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeBorderMidBrush}" />
+    <Setter Property="BorderThickness" Value="{DynamicResource DateTimeFlyoutBorderThickness}" />
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Border Name="Background" Background="{TemplateBinding Background}"
+                BorderBrush="{TemplateBinding BorderBrush}"
+                BorderThickness="{TemplateBinding BorderThickness}"
+                Padding="{DynamicResource DateTimeFlyoutBorderPadding}"
+                MaxHeight="398">
+          <Grid Name="ContentRoot" RowDefinitions="*,Auto">
+            <Grid Name="PickerContainer">
+              <!--Column Definitions set in code, ignore here-->
+              <Panel Name="MonthHost">
+                <ScrollViewer HorizontalScrollBarVisibility="Disabled"
+                              VerticalScrollBarVisibility="Hidden">
+                  <DateTimePickerPanel Name="MonthSelector"
+                                      PanelType="Month"
+                                      ItemHeight="{DynamicResource DatePickerFlyoutPresenterItemHeight}"
+                                      ShouldLoop="True" />
+                </ScrollViewer>
+                <RepeatButton Name="MonthUpButton"
+                              Classes="DateTimeFlyoutButtonStyle UpButton"/>
+                <RepeatButton Name="MonthDownButton"
+                              Classes="DateTimeFlyoutButtonStyle DownButton"/>
+              </Panel>
+              <Panel Name="DayHost">
+                <ScrollViewer HorizontalScrollBarVisibility="Disabled"
+                              VerticalScrollBarVisibility="Hidden">
+                  <DateTimePickerPanel Name="DaySelector"
+                                      PanelType="Day"
+                                      ItemHeight="{DynamicResource DatePickerFlyoutPresenterItemHeight}"
+                                      ShouldLoop="True" />
+                </ScrollViewer>
+                <RepeatButton Name="DayUpButton"
+                              Classes="DateTimeFlyoutButtonStyle UpButton"/>
+                <RepeatButton Name="DayDownButton"
+                              Classes="DateTimeFlyoutButtonStyle DownButton"/>
+              </Panel>
+              <Panel Name="YearHost">
+                <ScrollViewer HorizontalScrollBarVisibility="Disabled"
+                              VerticalScrollBarVisibility="Hidden">
+                  <DateTimePickerPanel Name="YearSelector"
+                                      PanelType="Year"
+                                      ItemHeight="{DynamicResource DatePickerFlyoutPresenterItemHeight}"
+                                      ShouldLoop="False" />
+                </ScrollViewer>
+                <RepeatButton Name="YearUpButton"
+                              Classes="DateTimeFlyoutButtonStyle UpButton"/>
+                <RepeatButton Name="YearDownButton"
+                              Classes="DateTimeFlyoutButtonStyle DownButton"/>
+              </Panel>
+              <Rectangle Name="HighlightRect" IsHitTestVisible="False" ZIndex="-1"
+                         Fill="{DynamicResource DatePickerFlyoutPresenterHighlightFill}"
+                         Grid.Column="0" Grid.ColumnSpan="5" VerticalAlignment="Center"
+                         Height="{DynamicResource DatePickerFlyoutPresenterHighlightHeight}" />
+              <Rectangle Name="FirstSpacer"
+                         Fill="{DynamicResource ThemeControlMidHighBrush}"
+                         HorizontalAlignment="Center"
+                         Width="{DynamicResource DatePickerSpacerThemeWidth}"
+                         Grid.Column="1" />
+              <Rectangle Name="SecondSpacer"
+                         Fill="{DynamicResource ThemeControlMidHighBrush}"
+                         HorizontalAlignment="Center"
+                         Width="{DynamicResource DatePickerSpacerThemeWidth}"
+                         Grid.Column="3" />
+            </Grid>
+            <Grid Grid.Row="1" Height="{DynamicResource DatePickerFlyoutPresenterAcceptDismissHostGridHeight}"
+                  Name="AcceptDismissGrid" ColumnDefinitions="*,*">
+              <Rectangle Height="{DynamicResource DatePickerSpacerThemeWidth}" VerticalAlignment="Top"
+                         Fill="{DynamicResource ThemeControlMidHighBrush}"
+                         Grid.ColumnSpan="2"/>
+              <Button Name="AcceptButton" Grid.Column="0" Classes="DateTimeFlyoutButtonStyle"
+                          HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
+                <Path Stroke="{Binding $parent[Button].Foreground}" StrokeLineCap="Round"
+                      StrokeThickness="0.75" Data="M0.5,8.5 5,13.5 15.5,3" />
+              </Button>
+              <Button Name="DismissButton" Grid.Column="1" Classes="DateTimeFlyoutButtonStyle"
+                         FontSize="16" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
+                <Path Stroke="{Binding $parent[Button].Foreground}" StrokeLineCap="Round"
+                      StrokeThickness="0.75" Data="M2,2 14,14 M2,14 14 2" />
+              </Button>
+            </Grid>
+          </Grid>
+        </Border>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+
+  <Style Selector="DatePickerPresenter /template/ Panel RepeatButton">
+    <Setter Property="IsVisible" Value="False" />
+  </Style>
+
+  <Style Selector="DatePickerPresenter /template/ Panel:pointerover RepeatButton">
+    <Setter Property="IsVisible" Value="True" />
+  </Style>
+  
+</Styles>
diff --git a/src/Avalonia.Themes.Default/DefaultTheme.xaml b/src/Avalonia.Themes.Default/DefaultTheme.xaml
index 4e63d1d223..e5b654b490 100644
--- a/src/Avalonia.Themes.Default/DefaultTheme.xaml
+++ b/src/Avalonia.Themes.Default/DefaultTheme.xaml
@@ -55,4 +55,7 @@
   <StyleInclude Source="resm:Avalonia.Themes.Default.NotificationCard.xaml?assembly=Avalonia.Themes.Default"/>
   <StyleInclude Source="resm:Avalonia.Themes.Default.NativeMenuBar.xaml?assembly=Avalonia.Themes.Default"/>
   <StyleInclude Source="resm:Avalonia.Themes.Default.ToggleSwitch.xaml?assembly=Avalonia.Themes.Default"/>
+  <StyleInclude Source="resm:Avalonia.Themes.Default.SplitView.xaml?assembly=Avalonia.Themes.Default"/>
+  <StyleInclude Source="resm:Avalonia.Themes.Default.DatePicker.xaml?assembly=Avalonia.Themes.Default"/>
+  <StyleInclude Source="resm:Avalonia.Themes.Default.TimePicker.xaml?assembly=Avalonia.Themes.Default"/>
 </Styles>
diff --git a/src/Avalonia.Themes.Default/SplitView.xaml b/src/Avalonia.Themes.Default/SplitView.xaml
new file mode 100644
index 0000000000..4a9a7be164
--- /dev/null
+++ b/src/Avalonia.Themes.Default/SplitView.xaml
@@ -0,0 +1,219 @@
+<Styles xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+
+  <Styles.Resources>
+    <x:Double x:Key="SplitViewOpenPaneThemeLength">320</x:Double>
+    <x:Double x:Key="SplitViewCompactPaneThemeLength">48</x:Double>
+
+    <!-- Not used here (directly) since they're strings, but preserving for reference
+        <x:String x:Key="SplitViewPaneAnimationOpenDuration">00:00:00.2</x:String>
+        <x:String x:Key="SplitViewPaneAnimationOpenPreDuration">00:00:00.19999</x:String>
+        <x:String x:Key="SplitViewPaneAnimationCloseDuration">00:00:00.1</x:String>-->
+  </Styles.Resources>
+
+  <Style Selector="SplitView">
+    <Setter Property="OpenPaneLength" Value="{DynamicResource SplitViewOpenPaneThemeLength}" />
+    <Setter Property="CompactPaneLength" Value="{DynamicResource SplitViewCompactPaneThemeLength}" />
+    <Setter Property="PaneBackground" Value="{DynamicResource ThemeControlHighlightLowBrush}" />
+  </Style>
+
+  <!-- Left -->
+  <Style Selector="SplitView:left">
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Grid Name="Container" Background="{TemplateBinding Background}">
+          <Grid.ColumnDefinitions>
+            <!-- why is this throwing a binding error? -->
+            <ColumnDefinition Width="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.PaneColumnGridLength}"/>
+            <ColumnDefinition Width="*"/>
+          </Grid.ColumnDefinitions>
+
+          <Panel Name="PART_PaneRoot" Background="{TemplateBinding PaneBackground}"
+                 ClipToBounds="True"
+                 HorizontalAlignment="Left"
+                 ZIndex="100">
+            <Border Child="{TemplateBinding Pane}"/>
+            <Rectangle Name="HCPaneBorder" Fill="{DynamicResource SystemControlForegroundTransparentBrush}" Width="1" HorizontalAlignment="Right"  />
+          </Panel>
+
+          <Panel Name="ContentRoot">
+            <Border Child="{TemplateBinding Content}" />
+            <Rectangle Name="LightDismissLayer"/>
+          </Panel>
+
+        </Grid>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+
+  <!-- Overlay -->
+  <Style Selector="SplitView:overlay:left /template/ Panel#PART_PaneRoot">
+    <Setter Property="Width" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.ClosedPaneWidth}" />
+    <!-- ColumnSpan should be 2 -->
+    <Setter Property="Grid.ColumnSpan" Value="1"/>
+    <Setter Property="Grid.Column" Value="0"/>
+  </Style>
+  <Style Selector="SplitView:overlay:left /template/ Panel#ContentRoot">
+    <Setter Property="Grid.Column" Value="1"/>
+    <Setter Property="Grid.ColumnSpan" Value="2"/>
+  </Style>
+
+  <!-- CompactInline -->
+  <Style Selector="SplitView:compactinline:left /template/ Panel#PART_PaneRoot">
+    <Setter Property="Grid.ColumnSpan" Value="1"/>
+    <Setter Property="Grid.Column" Value="0"/>
+    <Setter Property="Width" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.ClosedPaneWidth}" />
+  </Style>
+  <Style Selector="SplitView:compactinline:left /template/ Panel#ContentRoot">
+    <Setter Property="Grid.Column" Value="1"/>
+    <Setter Property="Grid.ColumnSpan" Value="1"/>
+  </Style>
+
+  <!-- CompactOverlay -->
+  <Style Selector="SplitView:compactoverlay:left /template/ Panel#PART_PaneRoot">
+    <!-- ColumnSpan should be 2 -->
+    <Setter Property="Grid.ColumnSpan" Value="1"/>
+    <Setter Property="Grid.Column" Value="0"/>
+    <Setter Property="Width" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.ClosedPaneWidth}" />
+  </Style>
+  <Style Selector="SplitView:compactoverlay:left /template/ Panel#ContentRoot">
+    <Setter Property="Grid.Column" Value="1"/>
+    <Setter Property="Grid.ColumnSpan" Value="1"/>
+  </Style>
+
+  <!-- Inline -->
+  <Style Selector="SplitView:inline:left /template/ Panel#PART_PaneRoot">
+    <Setter Property="Grid.ColumnSpan" Value="1"/>
+    <Setter Property="Grid.Column" Value="0"/>
+    <Setter Property="Width" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.ClosedPaneWidth}" />
+  </Style>
+  <Style Selector="SplitView:inline:left /template/ Panel#ContentRoot">
+    <Setter Property="Grid.Column" Value="1"/>
+    <Setter Property="Grid.ColumnSpan" Value="1"/>
+  </Style>
+
+  <!-- Right -->
+  <Style Selector="SplitView:right">
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Grid Name="Container" Background="{TemplateBinding Background}">
+          <Grid.ColumnDefinitions>
+            <ColumnDefinition Width="*"/>
+            <ColumnDefinition Width="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.PaneColumnGridLength}"/>
+          </Grid.ColumnDefinitions>
+
+          <Panel Name="PART_PaneRoot" Background="{TemplateBinding PaneBackground}"
+                 ClipToBounds="True"
+                 HorizontalAlignment="Right"
+                 ZIndex="100">
+            <Border Child="{TemplateBinding Pane}"/>
+            <Rectangle Name="HCPaneBorder"
+                       Fill="{DynamicResource SystemControlForegroundTransparentBrush}"
+                       Width="1" HorizontalAlignment="Left"  />
+          </Panel>
+
+          <Panel Name="ContentRoot">
+            <Border Child="{TemplateBinding Content}" />
+            <Rectangle Name="LightDismissLayer"/>
+          </Panel>
+
+        </Grid>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+
+  <!-- Overlay -->
+  <Style Selector="SplitView:overlay:right /template/ Panel#PART_PaneRoot">
+    <Setter Property="Width" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.ClosedPaneWidth}" />
+    <Setter Property="Grid.ColumnSpan" Value="2"/>
+    <Setter Property="Grid.Column" Value="1"/>
+  </Style>
+  <Style Selector="SplitView:overlay:right /template/ Panel#ContentRoot">
+    <Setter Property="Grid.Column" Value="0"/>
+    <Setter Property="Grid.ColumnSpan" Value="2"/>
+  </Style>
+
+  <!-- CompactInline -->
+  <Style Selector="SplitView:compactinline:right /template/ Panel#PART_PaneRoot">
+    <Setter Property="Grid.ColumnSpan" Value="1"/>
+    <Setter Property="Grid.Column" Value="1"/>
+    <Setter Property="Width" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.ClosedPaneWidth}" />
+  </Style>
+  <Style Selector="SplitView:compactinline:right /template/ Panel#ContentRoot">
+    <Setter Property="Grid.Column" Value="0"/>
+    <Setter Property="Grid.ColumnSpan" Value="1"/>
+  </Style>
+
+  <!-- CompactOverlay -->
+  <Style Selector="SplitView:compactoverlay:right /template/ Panel#PART_PaneRoot">
+    <Setter Property="Grid.ColumnSpan" Value="2"/>
+    <Setter Property="Grid.Column" Value="1"/>
+    <Setter Property="Width" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.ClosedPaneWidth}" />
+  </Style>
+  <Style Selector="SplitView:compactoverlay:right /template/ Panel#ContentRoot">
+    <Setter Property="Grid.Column" Value="0"/>
+    <Setter Property="Grid.ColumnSpan" Value="1"/>
+  </Style>
+
+  <!-- Inline -->
+  <Style Selector="SplitView:inline:right /template/ Panel#PART_PaneRoot">
+    <Setter Property="Grid.ColumnSpan" Value="1"/>
+    <Setter Property="Grid.Column" Value="1"/>
+    <Setter Property="Width" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.ClosedPaneWidth}" />
+  </Style>
+  <Style Selector="SplitView:inline:right /template/ Panel#ContentRoot">
+    <Setter Property="Grid.Column" Value="0"/>
+    <Setter Property="Grid.ColumnSpan" Value="1"/>
+  </Style>
+
+  <!-- Open/Close Pane animation  -->
+  <Style Selector="SplitView:open /template/ Panel#PART_PaneRoot">
+    <Setter Property="Transitions">
+      <Transitions>
+        <DoubleTransition Property="Width" Duration="00:00:00.2" Easing="0.1,0.9,0.2,1.0" />
+      </Transitions>
+    </Setter>
+    <Setter Property="Width" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=OpenPaneLength}" />
+  </Style>
+  <Style Selector="SplitView:open /template/ Rectangle#LightDismissLayer">
+    <Setter Property="Transitions">
+      <Transitions>
+        <DoubleTransition Property="Opacity" Duration="00:00:00.2" Easing="0.1,0.9,0.2,1.0" />
+      </Transitions>
+    </Setter>
+    <Setter Property="Opacity" Value="1.0"/>
+  </Style>
+
+  <Style Selector="SplitView:closed /template/ Panel#PART_PaneRoot">
+    <Setter Property="Transitions">
+      <Transitions>
+        <DoubleTransition Property="Width" Duration="00:00:00.1" Easing="0.1,0.9,0.2,1.0" />
+      </Transitions>
+    </Setter>
+    <Setter Property="Width" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TemplateSettings.ClosedPaneWidth}" />
+  </Style>
+  <Style Selector="SplitView:closed /template/ Rectangle#LightDismissLayer">
+    <Setter Property="Transitions">
+      <Transitions>
+        <DoubleTransition Property="Opacity" Duration="00:00:00.2" Easing="0.1,0.9,0.2,1.0" />
+      </Transitions>
+    </Setter>
+    <Setter Property="Opacity" Value="0.0"/>
+  </Style>
+
+  <Style Selector="SplitView /template/ Rectangle#LightDismissLayer">
+    <Setter Property="IsVisible" Value="False"/>
+    <Setter Property="Fill" Value="Transparent" />
+  </Style>
+  <Style Selector="SplitView:lightdismiss /template/ Rectangle#LightDismissLayer">
+    <Setter Property="Fill" Value="{DynamicResource SplitViewLightDismissOverlayBackground}" />
+  </Style>
+
+  <Style Selector="SplitView:overlay:open /template/ Rectangle#LightDismissLayer">
+    <Setter Property="IsVisible" Value="True"/>
+  </Style>
+  <Style Selector="SplitView:compactoverlay:open /template/ Rectangle#LightDismissLayer">
+    <Setter Property="IsVisible" Value="True"/>
+  </Style>
+
+</Styles>
diff --git a/src/Avalonia.Themes.Default/TabItem.xaml b/src/Avalonia.Themes.Default/TabItem.xaml
index 92482a564c..6e344ce58e 100644
--- a/src/Avalonia.Themes.Default/TabItem.xaml
+++ b/src/Avalonia.Themes.Default/TabItem.xaml
@@ -2,7 +2,7 @@
     <Style Selector="TabItem">
         <Setter Property="Background" Value="Transparent"/>
         <Setter Property="FontSize" Value="{DynamicResource FontSizeLarge}"/>
-        <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundLightBrush}"/>
+        <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundLowBrush}"/>
         <Setter Property="HorizontalContentAlignment" Value="Left"/>
         <Setter Property="Padding" Value="8"/>
         <Setter Property="Template">
diff --git a/src/Avalonia.Themes.Default/TimePicker.xaml b/src/Avalonia.Themes.Default/TimePicker.xaml
new file mode 100644
index 0000000000..6c4d0c97bd
--- /dev/null
+++ b/src/Avalonia.Themes.Default/TimePicker.xaml
@@ -0,0 +1,283 @@
+<!--
+// (c) Copyright Microsoft Corporation.
+// This source is subject to the Microsoft Public License (Ms-PL).
+// Please see http://go.microsoft.com/fwlink/?LinkID=131993 for details.
+// All other rights reserved.
+-->
+
+<Styles xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:sys="clr-namespace:System;assembly=netstandard">
+  <Styles.Resources>
+    <x:Double x:Key="TimePickerFlyoutPresenterItemHeight">40</x:Double>
+    <x:Double x:Key="TimePickerSpacerThemeWidth">1</x:Double>
+    <Thickness x:Key="TimePickerBorderThemeThickness">1</Thickness>
+    <Thickness x:Key="TimePickerTopHeaderMargin">0,0,0,4</Thickness>
+    <x:Double x:Key="TimePickerFlyoutPresenterHighlightHeight">40</x:Double>
+    <x:Double x:Key="TimePickerFlyoutPresenterAcceptDismissHostGridHeight">41</x:Double>
+    <x:Double x:Key="TimePickerThemeMinWidth">242</x:Double>
+    <x:Double x:Key="TimePickerThemeMaxWidth">456</x:Double>
+    <Thickness x:Key="TimePickerFlyoutPresenterItemPadding">0,3,0,6</Thickness>
+    <Thickness x:Key="TimePickerHostPadding">0,3,0,6</Thickness>
+  </Styles.Resources>
+
+  <Style Selector="ListBoxItem.DateTimePickerItem.HourItem">
+    <Setter Property="Padding" Value="{DynamicResource TimePickerFlyoutPresenterItemPadding}" />
+  </Style>
+  <Style Selector="ListBoxItem.DateTimePickerItem.MinuteItem">
+    <Setter Property="Padding" Value="{DynamicResource TimePickerFlyoutPresenterItemPadding}" />
+  </Style>
+  <Style Selector="ListBoxItem.DateTimePickerItem.TimePeriodItem">
+    <Setter Property="Padding" Value="{DynamicResource TimePickerFlyoutPresenterItemPadding}" />
+  </Style>
+
+  <Style Selector="TimePicker">    
+    <Setter Property="FontSize" Value="{DynamicResource FontSizeNormal}" />
+    <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundBrush}" />
+    <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}"/>
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeControlHighlightMidBrush}"/>
+    <Setter Property="BorderThickness" Value="{DynamicResource TimePickerBorderThemeThickness}"/>
+    <Setter Property="HorizontalAlignment" Value="Left" />
+    <Setter Property="VerticalAlignment" Value="Center" />
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Grid Name="LayoutRoot" Margin="{TemplateBinding Padding}" RowDefinitions="Auto,*">
+          <ContentPresenter x:Name="HeaderContentPresenter"
+                 Grid.Row="0"
+                 Content="{TemplateBinding Header}"
+                 ContentTemplate="{TemplateBinding HeaderTemplate}"
+                 Margin="{DynamicResource TimePickerTopHeaderMargin}"
+                 MaxWidth="{DynamicResource TimePickerThemeMaxWidth}"
+                 TextBlock.Foreground="{DynamicResource TimePickerHeaderForeground}"
+                 HorizontalAlignment="Stretch"
+                 VerticalAlignment="Top" />
+
+          <Button x:Name="FlyoutButton"
+                  Grid.Row="1"
+                  Foreground="{TemplateBinding Foreground}"
+                  Background="{TemplateBinding Background}"
+                  BorderBrush="{TemplateBinding BorderBrush}"
+                  BorderThickness="{TemplateBinding BorderThickness}"
+                  IsEnabled="{TemplateBinding IsEnabled}"
+                  MinWidth="{DynamicResource TimePickerThemeMinWidth}"
+                  MaxWidth="{DynamicResource TimePickerThemeMaxWidth}"
+                  HorizontalAlignment="Stretch"
+                  HorizontalContentAlignment="Stretch"
+                  VerticalAlignment="Top"
+                  VerticalContentAlignment="Stretch">
+            <Button.Template>
+              <ControlTemplate>
+                <ContentPresenter Name="ContentPresenter"
+                                BorderBrush="{TemplateBinding BorderBrush}"
+                                Background="{TemplateBinding Background}"
+                                BorderThickness="{TemplateBinding BorderThickness}"
+                                Content="{TemplateBinding Content}"
+                                TextBlock.Foreground="{TemplateBinding Foreground}"
+                                HorizontalContentAlignment="Stretch"
+                                VerticalContentAlignment="Stretch" />
+              </ControlTemplate>
+            </Button.Template>
+
+            <Grid Name="FlyoutButtonContentGrid">
+              <!--Ignore col defs here, set in code-->
+              <Border x:Name="FirstPickerHost" Grid.Column="0" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
+                <TextBlock x:Name="HourTextBlock"
+                    HorizontalAlignment="Center"
+                    Padding="{DynamicResource TimePickerHostPadding}"
+                    FontFamily="{TemplateBinding FontFamily}"
+                    FontWeight="{TemplateBinding FontWeight}"
+                    FontSize="{TemplateBinding FontSize}" />
+              </Border>
+
+              <Rectangle Name="FirstColumnDivider"
+                  Fill="{DynamicResource ThemeControlMidHighBrush}"
+                  HorizontalAlignment="Center"
+                  Width="{DynamicResource TimePickerSpacerThemeWidth}"
+                  Grid.Column="1" />
+
+              <Border x:Name="SecondPickerHost" Grid.Column="2" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
+                <TextBlock x:Name="MinuteTextBlock"
+                    HorizontalAlignment="Center"
+                    Padding="{DynamicResource TimePickerHostPadding}"
+                    FontFamily="{TemplateBinding FontFamily}"
+                    FontWeight="{TemplateBinding FontWeight}"
+                    FontSize="{TemplateBinding FontSize}"/>
+              </Border>
+
+              <Rectangle Name="SecondColumnDivider"
+                  Fill="{DynamicResource ThemeControlMidHighBrush}"
+                  HorizontalAlignment="Center"
+                  Width="{DynamicResource TimePickerSpacerThemeWidth}"
+                  Grid.Column="3" />
+
+              <Border x:Name="ThirdPickerHost" Grid.Column="4" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
+                <TextBlock x:Name="PeriodTextBlock"
+                    HorizontalAlignment="Center"
+                    Padding="{DynamicResource TimePickerHostPadding}"
+                    FontFamily="{TemplateBinding FontFamily}"
+                    FontWeight="{TemplateBinding FontWeight}"
+                    FontSize="{TemplateBinding FontSize}" />
+              </Border>
+            </Grid>
+          </Button>
+
+          <Popup Name="Popup" WindowManagerAddShadowHint="False"
+                 StaysOpen="False" PlacementTarget="{TemplateBinding}"
+                 PlacementMode="Bottom">
+            <TimePickerPresenter Name="PickerPresenter" />
+          </Popup>
+
+        </Grid>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+
+  <Style Selector="TimePicker:disabled /template/ ContentPresenter#HeaderContentPresenter">
+    <Setter Property="TextBlock.Foreground" Value="{DynamicResource ThemeForegroundBrush}"/>
+  </Style>
+  <Style Selector="TimePicker:disabled /template/ Rectangle">
+    <Setter Property="Opacity" Value="{DynamicResource ThemeDisabledOpacity}"/>
+  </Style>
+
+  <Style Selector="TimePicker /template/ Button#FlyoutButton:pointerover /template/ ContentPresenter">
+    <!--<Setter Property="Background" Value="{DynamicResource TimePickerButtonBackgroundPointerOver}"/>-->
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeControlHighBrush}"/>
+    <Setter Property="TextBlock.Foreground" Value="{DynamicResource ThemeForegroundBrush}"/>
+  </Style>
+
+  <Style Selector="TimePicker /template/ Button:pressed /template/ ContentPresenter">
+    <Setter Property="Background">
+      <SolidColorBrush Color="{DynamicResource ThemeControlMidHighColor}" Opacity="0.6" />
+    </Setter>
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeControlLowBrush}"/>
+    <Setter Property="TextBlock.Foreground" Value="{DynamicResource ThemeForegroundBrush}"/>
+  </Style>
+
+  <Style Selector="TimePicker /template/ Button:disabled /template/ ContentPresenter">
+    <!--<Setter Property="Background" Value="{DynamicResource TimePickerButtonBackgroundDisabled}"/>
+    <Setter Property="BorderBrush" Value="{DynamicResource TimePickerButtonBorderBrushDisabled}"/>
+    <Setter Property="TextBlock.Foreground" Value="{DynamicResource TimePickerButtonForegroundDisabled}"/>-->
+    <Setter Property="Opacity" Value="{DynamicResource ThemeDisabledOpacity}" />
+  </Style>
+
+  <Style Selector="TimePicker:hasnotime /template/ Button#FlyoutButton TextBlock">
+    <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundLowBrush}"/>
+  </Style>
+
+  <Style Selector="TimePickerPresenter">
+    <Setter Property="Width" Value="242" />
+    <Setter Property="MinWidth" Value="242" />
+    <Setter Property="MaxHeight" Value="398" />    
+    <Setter Property="FontWeight" Value="Normal" />
+    <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}" />
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeBorderMidBrush}" />
+    <Setter Property="BorderThickness" Value="{DynamicResource DateTimeFlyoutBorderThickness}" />
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Border Name="Background"
+                Background="{TemplateBinding Background}"
+                BorderBrush="{TemplateBinding BorderBrush}"
+                BorderThickness="{TemplateBinding BorderThickness}"
+                Padding="{DynamicResource DateTimeFlyoutBorderPadding}"
+                MaxHeight="398">
+          <Grid Name="ContentPanel" RowDefinitions="*,Auto">
+            <Grid Name="PickerContainer">
+              <!--Ignore col defs here, set in code-->
+              <Panel Name="HourHost" Grid.Column="0">
+                <ScrollViewer HorizontalScrollBarVisibility="Disabled"
+                              VerticalScrollBarVisibility="Hidden">
+                  <DateTimePickerPanel Name="HourSelector"
+                                          PanelType="Hour"
+                                          ShouldLoop="True"
+                                          ItemHeight="{DynamicResource TimePickerFlyoutPresenterItemHeight}"/>
+                </ScrollViewer>
+                <RepeatButton Name="HourUpButton"
+                              Classes="DateTimeFlyoutButtonStyle UpButton"/>
+                <RepeatButton Name="HourDownButton"
+                              Classes="DateTimeFlyoutButtonStyle DownButton"/>
+
+              </Panel>
+
+              <Panel Name="MinuteHost" Grid.Column="2">
+                <ScrollViewer HorizontalScrollBarVisibility="Disabled"
+                              VerticalScrollBarVisibility="Hidden">
+                  <DateTimePickerPanel Name="MinuteSelector"
+                                          PanelType="Minute"
+                                          ShouldLoop="True"
+                                          ItemHeight="{DynamicResource TimePickerFlyoutPresenterItemHeight}"/>
+                </ScrollViewer>
+                <RepeatButton Name="MinuteUpButton"
+                              Classes="DateTimeFlyoutButtonStyle UpButton"/>
+                <RepeatButton Name="MinuteDownButton"
+                              Classes="DateTimeFlyoutButtonStyle DownButton"/>
+
+              </Panel>
+
+              <Panel Name="PeriodHost" Grid.Column="4">
+                <ScrollViewer HorizontalScrollBarVisibility="Disabled"
+                              VerticalScrollBarVisibility="Hidden">
+                  <DateTimePickerPanel Name="PeriodSelector"
+                                          PanelType="TimePeriod"
+                                          ShouldLoop="False"
+                                          ItemHeight="{DynamicResource TimePickerFlyoutPresenterItemHeight}"/>
+                </ScrollViewer>
+                <RepeatButton Name="PeriodUpButton"
+                              Classes="DateTimeFlyoutButtonStyle UpButton"/>
+                <RepeatButton Name="PeriodDownButton"
+                              Classes="DateTimeFlyoutButtonStyle DownButton"/>
+
+              </Panel>
+
+              <Rectangle x:Name="HighlightRect" ZIndex="-1"
+                      Fill="{DynamicResource TimePickerFlyoutPresenterHighlightFill}"
+                      Grid.Column="0"
+                      Grid.ColumnSpan="5"
+                      VerticalAlignment="Center"
+                      Height="{DynamicResource TimePickerFlyoutPresenterHighlightHeight}" />
+
+              <Rectangle Name="FirstSpacer"
+                  Fill="{DynamicResource ThemeControlMidHighBrush}"
+                  HorizontalAlignment="Center"
+                  Width="{DynamicResource TimePickerSpacerThemeWidth}"
+                  Grid.Column="1" />
+
+              <Rectangle Name="SecondSpacer"
+                  Fill="{DynamicResource ThemeControlMidHighBrush}"
+                  HorizontalAlignment="Center"
+                  Width="{DynamicResource TimePickerSpacerThemeWidth}"
+                  Grid.Column="3" />
+            </Grid>
+
+            <Grid Grid.Row="1" Height="{DynamicResource TimePickerFlyoutPresenterAcceptDismissHostGridHeight}"
+                  Name="AcceptDismissHostGrid" ColumnDefinitions="*,*">
+              <Rectangle Height="{DynamicResource TimePickerSpacerThemeWidth}"
+                      VerticalAlignment="Top"
+                      Fill="{DynamicResource ThemeControlMidHighBrush}"
+                      Grid.ColumnSpan="2" />
+              <Button Name="AcceptButton" Grid.Column="0" Classes="DateTimeFlyoutButtonStyle"
+                          HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
+                <Path Stroke="{Binding $parent[Button].Foreground}" StrokeLineCap="Round"
+                      StrokeThickness="0.75" Data="M0.5,8.5 5,13.5 15.5,3" />
+              </Button>
+              <Button Name="DismissButton" Grid.Column="1" Classes="DateTimeFlyoutButtonStyle"
+                         FontSize="16" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
+                <Path Stroke="{Binding $parent[Button].Foreground}" StrokeLineCap="Round"
+                      StrokeThickness="0.75" Data="M2,2 14,14 M2,14 14 2" />
+              </Button>
+            </Grid>
+
+          </Grid>
+        </Border>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+
+  <Style Selector="TimePickerPresenter /template/ Panel RepeatButton">
+    <Setter Property="IsVisible" Value="False" />
+  </Style>
+
+  <Style Selector="TimePickerPresenter /template/ Panel:pointerover RepeatButton">
+    <Setter Property="IsVisible" Value="True" />
+  </Style>
+  
+</Styles>
diff --git a/src/Avalonia.Themes.Default/ToggleSwitch.xaml b/src/Avalonia.Themes.Default/ToggleSwitch.xaml
index ded121f5f6..5c0a3b99f3 100644
--- a/src/Avalonia.Themes.Default/ToggleSwitch.xaml
+++ b/src/Avalonia.Themes.Default/ToggleSwitch.xaml
@@ -6,8 +6,40 @@
     <GridLength x:Key="ToggleSwitchPreContentMargin">6</GridLength>
     <GridLength x:Key="ToggleSwitchPostContentMargin">6</GridLength>
     <x:Double x:Key="ToggleSwitchThemeMinWidth">154</x:Double>
-    <x:Double x:Key="KnobOnPosition">20</x:Double>
-    <x:Double x:Key="KnobOffPosition">0</x:Double>
+    <Thickness x:Key="ToggleSwitchOnStrokeThickness">0</Thickness>
+    <Thickness x:Key="ToggleSwitchOuterBorderStrokeThickness">1</Thickness>
+    <SolidColorBrush x:Key="ToggleSwitchContentForeground" Color="{DynamicResource ThemeForegroundColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchContentForegroundDisabled" Color="{DynamicResource ThemeForegroundLowColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchHeaderForeground" Color="{DynamicResource ThemeForegroundColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchHeaderForegroundDisabled" Color="{DynamicResource ThemeForegroundLowColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchContainerBackground" Color="{DynamicResource ThemeControlTransparentColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchContainerBackgroundPointerOver" Color="{DynamicResource ThemeControlTransparentColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchContainerBackgroundPressed" Color="{DynamicResource ThemeControlTransparentColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchContainerBackgroundDisabled" Color="{DynamicResource ThemeControlTransparentColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchFillOff" Color="{DynamicResource ThemeControlTransparentColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchFillOffPointerOver" Color="{DynamicResource ThemeControlTransparentColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchFillOffPressed" Color="{DynamicResource ThemeControlMidHighColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchFillOffDisabled" Color="{DynamicResource ThemeControlTransparentColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchStrokeOff" Color="{DynamicResource ThemeBorderMidColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchStrokeOffPointerOver" Color="{DynamicResource ThemeBorderHighColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchStrokeOffPressed" Color="{DynamicResource ThemeBorderHighColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchStrokeOffDisabled" Color="{DynamicResource ThemeForegroundLowColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchFillOn" Color="{DynamicResource ThemeAccentColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchFillOnPointerOver" Color="{DynamicResource ThemeAccentColor2}" />
+    <SolidColorBrush x:Key="ToggleSwitchFillOnPressed" Color="{DynamicResource ThemeAccentColor3}" />
+    <SolidColorBrush x:Key="ToggleSwitchFillOnDisabled" Color="{DynamicResource ThemeForegroundLowColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchStrokeOn" Color="{DynamicResource ThemeAccentColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchStrokeOnPointerOver" Color="{DynamicResource ThemeAccentColor2}" />
+    <SolidColorBrush x:Key="ToggleSwitchStrokeOnPressed" Color="{DynamicResource ThemeAccentColor3}" />
+    <SolidColorBrush x:Key="ToggleSwitchStrokeOnDisabled" Color="{DynamicResource ThemeForegroundLowColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchKnobFillOff" Color="{DynamicResource ThemeBorderMidColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchKnobFillOffPointerOver" Color="{DynamicResource ThemeBorderHighColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchKnobFillOffPressed" Color="{DynamicResource ThemeBorderHighColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchKnobFillOffDisabled" Color="{DynamicResource ThemeForegroundLowColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchKnobFillOn" Color="{DynamicResource HighlightForegroundColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchKnobFillOnPointerOver" Color="{DynamicResource HighlightForegroundColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchKnobFillOnPressed" Color="{DynamicResource HighlightForegroundColor}" />
+    <SolidColorBrush x:Key="ToggleSwitchKnobFillOnDisabled" Color="{DynamicResource HighlightForegroundColor}" />
   </Styles.Resources>
   <Design.PreviewWith>
     <StackPanel Margin="20" Width="250" Spacing="24" >
@@ -148,16 +180,13 @@
 
   <Style Selector="ToggleSwitch /template/ Ellipse#SwitchKnobOn">
     <Setter Property="Fill" Value="{DynamicResource ToggleSwitchKnobFillOn}"/>
-    <Setter Property="Stroke" Value="{DynamicResource ToggleSwitchKnobStrokeOn}"/>
   </Style>
 
   <Style Selector="ToggleSwitch /template/ Ellipse#SwitchKnobOff">
     <Setter Property="Fill" Value="{DynamicResource ToggleSwitchKnobFillOff}"/>
-    <Setter Property="Stroke" Value="{DynamicResource ToggleSwitchKnobStrokeOff}"/>
   </Style>
 
   <Style Selector="ToggleSwitch /template/ Grid#MovingKnobs">
-    <Setter Property="Canvas.Left" Value="{DynamicResource KnobOffPosition}"/>
     <Setter Property="Transitions">
       <Transitions>
         <DoubleTransition Property="Canvas.Left" Duration="0:0:0.2" Easing="CubicEaseOut"/>
@@ -235,10 +264,6 @@
   </Style>
 
   <!-- CheckedState -->
-  <Style Selector="ToggleSwitch:checked /template/ Grid#MovingKnobs">
-    <Setter Property="Canvas.Left" Value="{DynamicResource KnobOnPosition}"/>
-  </Style>
-
   <Style Selector="ToggleSwitch:checked /template/ Border#OuterBorder">
     <Setter Property="Opacity" Value="0"/>
   </Style>
@@ -264,10 +289,6 @@
   </Style>
 
   <!--UncheckedState -->
-  <Style Selector="ToggleSwitch:unchecked /template/ Grid#MovingKnobs">
-    <Setter Property="Canvas.Left" Value="{DynamicResource KnobOffPosition}"/>
-  </Style>
-
   <Style Selector="ToggleSwitch:unchecked /template/ Border#OuterBorder">
     <Setter Property="Opacity" Value="1"/>
   </Style>
diff --git a/src/Avalonia.Themes.Fluent/Accents/Base.xaml b/src/Avalonia.Themes.Fluent/Accents/Base.xaml
index 8358297f8b..46488c1c57 100644
--- a/src/Avalonia.Themes.Fluent/Accents/Base.xaml
+++ b/src/Avalonia.Themes.Fluent/Accents/Base.xaml
@@ -6,12 +6,12 @@
     <!-- SystemColor Color Resources (Reflect OS High Contrast Settings) -->
     <Color x:Key="SystemColorButtonFaceColor">#FFF0F0F0</Color>
     <Color x:Key="SystemColorButtonTextColor">#FF000000</Color>
-    <Color x:Key="SystemColorGrayText">#FF6D6D6D</Color>
-    <Color x:Key="SystemColorHighlight">#FF3399FF</Color>
-    <Color x:Key="SystemColorHighlightText">#FFFFFFFF</Color>
-    <Color x:Key="SystemColorHotlight">#FF0066CC</Color>
-    <Color x:Key="SystemColorWindow">#FFFFFFFF</Color>
-    <Color x:Key="SystemColorWindowText">#FF000000</Color>
+    <Color x:Key="SystemColorGrayTextColor">#FF6D6D6D</Color>
+    <Color x:Key="SystemColorHighlightColor">#FF3399FF</Color>
+    <Color x:Key="SystemColorHighlightTextColor">#FFFFFFFF</Color>
+    <Color x:Key="SystemColorHotlightColor">#FF0066CC</Color>
+    <Color x:Key="SystemColorWindowColor">#FFFFFFFF</Color>
+    <Color x:Key="SystemColorWindowTextColor">#FF000000</Color>
     <FontFamily x:Key="ContentControlThemeFontFamily">avares://Avalonia.Themes.Fluent/Assets#Roboto</FontFamily>
     <sys:Double x:Key="ControlContentThemeFontSize">14</sys:Double>
 
diff --git a/src/Avalonia.Themes.Fluent/Accents/FluentControlResourcesDark.xaml b/src/Avalonia.Themes.Fluent/Accents/FluentControlResourcesDark.xaml
index 653e4733cb..4d21068492 100644
--- a/src/Avalonia.Themes.Fluent/Accents/FluentControlResourcesDark.xaml
+++ b/src/Avalonia.Themes.Fluent/Accents/FluentControlResourcesDark.xaml
@@ -437,6 +437,15 @@
     <StaticResource x:Key="CalendarViewCalendarItemRevealBorderBrush" ResourceKey="SystemControlTransparentRevealBorderBrush" />
     <StaticResource x:Key="CalendarViewNavigationButtonBorderBrushPointerOver" ResourceKey="SystemControlHighlightTransparentBrush" />
     <StaticResource x:Key="CalendarViewNavigationButtonBorderBrush" ResourceKey="SystemControlTransparentBrush" />
+    
+    <!--Resources for NotificationCard.xaml -->
+    <SolidColorBrush x:Key="NotificationCardBackgroundBrush" Color="#444444" Opacity="0.75"/>
+    <SolidColorBrush x:Key="NotificationCardProgressBackgroundBrush" Color="#9A9A9A" />
+    <SolidColorBrush x:Key="NotificationCardInformationBackgroundBrush" Color="#007ACC" Opacity="0.75"/>
+    <SolidColorBrush x:Key="NotificationCardSuccessBackgroundBrush" Color="#1F9E45" Opacity="0.75"/>
+    <SolidColorBrush x:Key="NotificationCardWarningBackgroundBrush" Color="#FDB328" Opacity="0.75"/>
+    <SolidColorBrush x:Key="NotificationCardErrorBackgroundBrush" Color="#BD202C" Opacity="0.75"/>
+    
     <!-- Resources for RadioButton.xaml -->
     <x:Double x:Key="RadioButtonBorderThemeThickness">1</x:Double>
     <StaticResource x:Key="RadioButtonForeground" ResourceKey="SystemControlForegroundBaseHighBrush" />
diff --git a/src/Avalonia.Themes.Fluent/AutoCompleteBox.xaml b/src/Avalonia.Themes.Fluent/AutoCompleteBox.xaml
index 0d5d733cd9..7dc3bda133 100644
--- a/src/Avalonia.Themes.Fluent/AutoCompleteBox.xaml
+++ b/src/Avalonia.Themes.Fluent/AutoCompleteBox.xaml
@@ -52,13 +52,12 @@
             <Border Name="PART_SuggestionsContainer"
                     Padding="{DynamicResource AutoCompleteListMargin}"
                     BorderThickness="{DynamicResource AutoCompleteListBorderThemeThickness}"
-                    BorderBrush="{DynamicResource AutoSuggestBoxSuggestionsListBorderBrush}"
+                    BorderBrush="{DynamicResource AutoCompleteBoxSuggestionsListBorderBrush}"
                     Background="{DynamicResource AutoCompleteBoxSuggestionsListBackground}"
                     CornerRadius="{DynamicResource OverlayCornerRadius}">
               <ListBox Name="PART_SelectingItemsControl"
                        BorderThickness="0"
                        Background="Transparent"
-                       Foreground="{DynamicResource AutoCompleteBoxSuggestionsListForeground}"
                        ItemTemplate="{TemplateBinding ItemTemplate}"
                        Margin="{DynamicResource AutoCompleteListPadding}" />
             </Border>
diff --git a/src/Avalonia.Themes.Fluent/ButtonSpinner.xaml b/src/Avalonia.Themes.Fluent/ButtonSpinner.xaml
index 62d1653de7..82265ea282 100644
--- a/src/Avalonia.Themes.Fluent/ButtonSpinner.xaml
+++ b/src/Avalonia.Themes.Fluent/ButtonSpinner.xaml
@@ -8,7 +8,11 @@
       <StackPanel Spacing="20">
         <ButtonSpinner ButtonSpinnerLocation="Right"
                        Content="Right disabled inline spinner"
-                       AllowSpin="False" />
+                       AllowSpin="False">
+          <DataValidationErrors.Error>
+            <sys:Exception />
+          </DataValidationErrors.Error>
+        </ButtonSpinner>
         <ButtonSpinner ButtonSpinnerLocation="Left"
                        Content="Left spinner" />
         <ButtonSpinner ShowButtonSpinner="False"
@@ -133,7 +137,7 @@
 
   <!--  Error state  -->
   <Style Selector="ButtonSpinner:error">
-    <Setter Property="BorderBrush" Value="{DynamicResource ErrorBrush}" />
+    <Setter Property="BorderBrush" Value="{DynamicResource SystemErrorTextColor}" />
   </Style>
 
 </Styles>
diff --git a/src/Avalonia.Themes.Fluent/CalendarButton.xaml b/src/Avalonia.Themes.Fluent/CalendarButton.xaml
index 87082ef21e..ca538e4b0a 100644
--- a/src/Avalonia.Themes.Fluent/CalendarButton.xaml
+++ b/src/Avalonia.Themes.Fluent/CalendarButton.xaml
@@ -67,7 +67,7 @@
 
   <!-- Adjusted :selected to look like :today from DayItem -->
   <Style Selector="CalendarButton:selected /template/ Border#Root">
-    <Setter Property="Background" Value="{DynamicResource SystemAccentBrush}"/>
+    <Setter Property="Background" Value="{DynamicResource SystemAccentColor}"/>
   </Style>
   <Style Selector="CalendarButton:selected /template/ Border#Border">
     <Setter Property="BorderBrush" Value="{DynamicResource CalendarViewSelectedBorderBrush}"/>
diff --git a/src/Avalonia.Themes.Fluent/CalendarDatePicker.xaml b/src/Avalonia.Themes.Fluent/CalendarDatePicker.xaml
index 4af47fccf6..bca61cbd0e 100644
--- a/src/Avalonia.Themes.Fluent/CalendarDatePicker.xaml
+++ b/src/Avalonia.Themes.Fluent/CalendarDatePicker.xaml
@@ -13,6 +13,10 @@
       <CalendarDatePicker/>
     </Border>
   </Design.PreviewWith>
+
+  <Styles.Resources>
+    <sys:Double x:Key="CalendarDatePickerCurrentDayFontSize">12</sys:Double>
+  </Styles.Resources>
   
   <Style Selector="CalendarDatePicker">
 
@@ -70,7 +74,7 @@
                                Grid.Row="1"
                                Grid.ColumnSpan="4"
                                Grid.RowSpan="3"
-                               FontSize="{DynamicResource FontSizeSmall}"
+                               FontSize="{StaticResource CalendarDatePickerCurrentDayFontSize}"
                                Text="{Binding Source={x:Static sys:DateTime.Today}, Path=Day}"/>
 
                     <Ellipse HorizontalAlignment="Center" VerticalAlignment="Center" Fill="{DynamicResource SystemControlBackgroundChromeBlackHighBrush}" StrokeThickness="0" Grid.ColumnSpan="4" Width="3" Height="3"/>
diff --git a/src/Avalonia.Themes.Fluent/DataValidationErrors.xaml b/src/Avalonia.Themes.Fluent/DataValidationErrors.xaml
index f4145a51f5..88c6b661f1 100644
--- a/src/Avalonia.Themes.Fluent/DataValidationErrors.xaml
+++ b/src/Avalonia.Themes.Fluent/DataValidationErrors.xaml
@@ -1,5 +1,16 @@
 <Style xmlns="https://github.com/avaloniaui" 
-       Selector="DataValidationErrors">
+       Selector="DataValidationErrors"
+       xmlns:sys="clr-namespace:System;assembly=netstandard">
+  <Design.PreviewWith>
+    <Border Padding="20"> 
+      <TextBox Text="Sample">
+        <DataValidationErrors.Error>
+          <sys:Exception/> 
+        </DataValidationErrors.Error>
+      </TextBox>
+    </Border>
+  </Design.PreviewWith>
+    
   <Setter Property="Template">
     <ControlTemplate>
       <DockPanel LastChildFill="True">
@@ -24,14 +35,13 @@
               Background="Transparent">
         <Canvas.Styles>
           <Style Selector="ToolTip">
-            <Setter Property="Background" Value="{DynamicResource ErrorLowBrush}"/>
-            <Setter Property="BorderBrush" Value="{DynamicResource ErrorBrush}"/>
+            <Setter Property="BorderBrush" Value="{DynamicResource SystemControlErrorTextForegroundBrush}"/>
           </Style>
         </Canvas.Styles>
         <ToolTip.Tip>
           <ItemsControl Items="{Binding}"/>
         </ToolTip.Tip>
-        <Path Data="M14,7 A7,7 0 0,0 0,7 M0,7 A7,7 0 1,0 14,7 M7,3l0,5 M7,9l0,2" Stroke="{DynamicResource ErrorBrush}" StrokeThickness="2"/>
+        <Path Data="M14,7 A7,7 0 0,0 0,7 M0,7 A7,7 0 1,0 14,7 M7,3l0,5 M7,9l0,2" Stroke="{DynamicResource SystemControlErrorTextForegroundBrush}" StrokeThickness="2"/>
       </Canvas>
     </DataTemplate>
   </Setter>
diff --git a/src/Avalonia.Themes.Fluent/MenuItem.xaml b/src/Avalonia.Themes.Fluent/MenuItem.xaml
index 5123ba4cf2..e1f7ea2279 100644
--- a/src/Avalonia.Themes.Fluent/MenuItem.xaml
+++ b/src/Avalonia.Themes.Fluent/MenuItem.xaml
@@ -50,7 +50,6 @@
 
   <Style Selector="MenuItem">
     <Setter Property="Background" Value="{DynamicResource MenuFlyoutItemBackground}" />
-    <Setter Property="BorderBrush" Value="{DynamicResource MenuFlyoutItemRevealBorderBrush}" />
     <Setter Property="Foreground" Value="{DynamicResource MenuFlyoutItemForeground}" />
     <Setter Property="Padding" Value="{DynamicResource MenuFlyoutItemThemePadding}" />
     <Setter Property="FontSize" Value="{DynamicResource ControlContentThemeFontSize}" />
@@ -212,7 +211,6 @@
 
   <Style Selector="MenuItem:selected /template/ Border#PART_LayoutRoot">
     <Setter Property="Background" Value="{DynamicResource MenuFlyoutItemBackgroundPointerOver}" />
-    <Setter Property="BorderBrush" Value="{DynamicResource MenuFlyoutItemBorderBrushPointerOver}" />
   </Style>
   <Style Selector="MenuItem:selected /template/ TextBlock#PART_InputGestureText">
     <Setter Property="Foreground" Value="{DynamicResource MenuFlyoutItemKeyboardAcceleratorTextForegroundPointerOver}" />
@@ -224,7 +222,6 @@
   <!--  Listen for PART_LayoutRoot:pointerover, so it will not be triggered when subitem is pressed  -->
   <Style Selector="MenuItem:pressed /template/ Border#PART_LayoutRoot:pointerover">
     <Setter Property="Background" Value="{DynamicResource MenuFlyoutItemBackgroundPressed}" />
-    <Setter Property="BorderBrush" Value="{DynamicResource MenuFlyoutItemBorderBrushPressed}" />
   </Style>
   <Style Selector="MenuItem:pressed /template/ Border#PART_LayoutRoot:pointerover TextBlock#PART_InputGestureText">
     <Setter Property="Foreground" Value="{DynamicResource MenuFlyoutItemKeyboardAcceleratorTextForegroundPressed}" />
@@ -235,7 +232,6 @@
 
   <Style Selector="MenuItem:disabled">
     <Setter Property="Background" Value="{DynamicResource MenuFlyoutItemBackgroundDisabled}" />
-    <Setter Property="BorderBrush" Value="{DynamicResource MenuFlyoutItemBorderBrushDisabled}" />
   </Style>
   <Style Selector="MenuItem:disabled /template/ TextBlock#PART_InputGestureText">
     <Setter Property="Foreground" Value="{DynamicResource MenuFlyoutItemKeyboardAcceleratorTextForegroundDisabled}" />
diff --git a/src/Avalonia.Themes.Fluent/TextBox.xaml b/src/Avalonia.Themes.Fluent/TextBox.xaml
index a72c7586e9..6a26e7dcae 100644
--- a/src/Avalonia.Themes.Fluent/TextBox.xaml
+++ b/src/Avalonia.Themes.Fluent/TextBox.xaml
@@ -1,4 +1,13 @@
 <Styles xmlns="https://github.com/avaloniaui" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+  <Design.PreviewWith>
+    <Border Padding="20">
+      <TextBox Text="Sample"
+               FontSize="20"
+               Width="100"
+               TextAlignment="Center"/>
+    </Border>
+  </Design.PreviewWith>
+  
   <Styles.Resources>
     <Thickness x:Key="TextBoxTopHeaderMargin">0,0,0,4</Thickness>
   </Styles.Resources>
@@ -42,7 +51,7 @@
               <DockPanel>
                 <TextBlock Name="floatingWatermark"
                            Foreground="{DynamicResource SystemAccentColor}"
-                           FontSize="{DynamicResource FontSizeSmall}"
+                           FontSize="{TemplateBinding FontSize}"
                            Text="{TemplateBinding Watermark}"
                            DockPanel.Dock="Top">
                   <TextBlock.IsVisible>
@@ -140,7 +149,7 @@
 
 
   <Style Selector="TextBox:error /template/ Border#border">
-    <Setter Property="BorderBrush" Value="{DynamicResource ErrorBrush}"/>
+    <Setter Property="BorderBrush" Value="{DynamicResource SystemControlErrorTextForegroundBrush}"/>
   </Style>
 
   <Style Selector="TextBox /template/ DockPanel">
diff --git a/src/Avalonia.Themes.Fluent/ToggleSwitch.xaml b/src/Avalonia.Themes.Fluent/ToggleSwitch.xaml
index 4309edefe3..56249f5986 100644
--- a/src/Avalonia.Themes.Fluent/ToggleSwitch.xaml
+++ b/src/Avalonia.Themes.Fluent/ToggleSwitch.xaml
@@ -6,8 +6,6 @@
     <GridLength x:Key="ToggleSwitchPreContentMargin">6</GridLength>
     <GridLength x:Key="ToggleSwitchPostContentMargin">6</GridLength>
     <x:Double x:Key="ToggleSwitchThemeMinWidth">154</x:Double>
-    <x:Double x:Key="KnobOnPosition">20</x:Double>
-    <x:Double x:Key="KnobOffPosition">0</x:Double>
   </Styles.Resources>
   <Design.PreviewWith>
     <StackPanel Margin="20" Width="250" Spacing="24" >
@@ -148,12 +146,10 @@
 
   <Style Selector="ToggleSwitch /template/ Ellipse#SwitchKnobOn">
     <Setter Property="Fill" Value="{DynamicResource ToggleSwitchKnobFillOn}"/>
-    <Setter Property="Stroke" Value="{DynamicResource ToggleSwitchKnobStrokeOn}"/>
   </Style>
 
   <Style Selector="ToggleSwitch /template/ Ellipse#SwitchKnobOff">
     <Setter Property="Fill" Value="{DynamicResource ToggleSwitchKnobFillOff}"/>
-    <Setter Property="Stroke" Value="{DynamicResource ToggleSwitchKnobStrokeOff}"/>
   </Style>
 
   <Style Selector="ToggleSwitch:not(:dragging) /template/ Grid#MovingKnobs">
diff --git a/src/Avalonia.Visuals/Media/TextFormatting/TextFormatterImpl.cs b/src/Avalonia.Visuals/Media/TextFormatting/TextFormatterImpl.cs
index 9318fcc68e..b116249fd4 100644
--- a/src/Avalonia.Visuals/Media/TextFormatting/TextFormatterImpl.cs
+++ b/src/Avalonia.Visuals/Media/TextFormatting/TextFormatterImpl.cs
@@ -31,7 +31,8 @@ namespace Avalonia.Media.TextFormatting
                 case TextWrapping.WrapWithOverflow:
                 case TextWrapping.Wrap:
                     {
-                        textLine = PerformTextWrapping(textRuns, textRange, paragraphWidth, paragraphProperties);
+                        textLine = PerformTextWrapping(textRuns, textRange, paragraphWidth, paragraphProperties,
+                            nextLineBreak);
                         break;
                     }
                 default:
@@ -118,7 +119,7 @@ namespace Avalonia.Media.TextFormatting
         /// <param name="textRuns">The text run's.</param>
         /// <param name="length">The length to split at.</param>
         /// <returns>The split text runs.</returns>
-        internal static SplitTextRunsResult SplitTextRuns(IReadOnlyList<ShapedTextCharacters> textRuns, int length)
+        internal static SplitTextRunsResult SplitTextRuns(List<ShapedTextCharacters> textRuns, int length)
         {
             var currentLength = 0;
 
@@ -134,13 +135,13 @@ namespace Avalonia.Media.TextFormatting
 
                 var firstCount = currentRun.GlyphRun.Characters.Length >= 1 ? i + 1 : i;
 
-                var first = new ShapedTextCharacters[firstCount];
+                var first = new List<ShapedTextCharacters>(firstCount);
 
                 if (firstCount > 1)
                 {
                     for (var j = 0; j < i; j++)
                     {
-                        first[j] = textRuns[j];
+                        first.Add(textRuns[j]);
                     }
                 }
 
@@ -148,7 +149,7 @@ namespace Avalonia.Media.TextFormatting
 
                 if (currentLength + currentRun.GlyphRun.Characters.Length == length)
                 {
-                    var second = new ShapedTextCharacters[secondCount];
+                    var second = new List<ShapedTextCharacters>(secondCount);
 
                     var offset = currentRun.GlyphRun.Characters.Length > 1 ? 1 : 0;
 
@@ -156,11 +157,11 @@ namespace Avalonia.Media.TextFormatting
                     {
                         for (var j = 0; j < secondCount; j++)
                         {
-                            second[j] = textRuns[i + j + offset];
+                            second.Add(textRuns[i + j + offset]);
                         }
                     }
 
-                    first[i] = currentRun;
+                    first.Add(currentRun);
 
                     return new SplitTextRunsResult(first, second);
                 }
@@ -168,22 +169,22 @@ namespace Avalonia.Media.TextFormatting
                 {
                     secondCount++;
 
-                    var second = new ShapedTextCharacters[secondCount];
+                    var second = new List<ShapedTextCharacters>(secondCount);
+
+                    var split = currentRun.Split(length - currentLength);
+
+                    first.Add(split.First);
+
+                    second.Add(split.Second);
 
                     if (secondCount > 0)
                     {
                         for (var j = 1; j < secondCount; j++)
                         {
-                            second[j] = textRuns[i + j];
+                            second.Add(textRuns[i + j]);
                         }
                     }
 
-                    var split = currentRun.Split(length - currentLength);
-
-                    first[i] = split.First;
-
-                    second[0] = split.Second;
-
                     return new SplitTextRunsResult(first, second);
                 }
             }
@@ -201,7 +202,7 @@ namespace Avalonia.Media.TextFormatting
         /// <returns>
         /// The formatted text runs.
         /// </returns>
-        private static IReadOnlyList<ShapedTextCharacters> FetchTextRuns(ITextSource textSource,
+        private static List<ShapedTextCharacters> FetchTextRuns(ITextSource textSource,
             int firstTextSourceIndex, TextLineBreak previousLineBreak, out TextLineBreak nextLineBreak)
         {
             nextLineBreak = default;
@@ -212,8 +213,10 @@ namespace Avalonia.Media.TextFormatting
 
             if (previousLineBreak != null)
             {
-                foreach (var shapedCharacters in previousLineBreak.RemainingCharacters)
+                for (var index = 0; index < previousLineBreak.RemainingCharacters.Count; index++)
                 {
+                    var shapedCharacters = previousLineBreak.RemainingCharacters[index];
+
                     if (shapedCharacters == null)
                     {
                         continue;
@@ -225,6 +228,14 @@ namespace Avalonia.Media.TextFormatting
                     {
                         var splitResult = SplitTextRuns(textRuns, currentLength + runLineBreak.PositionWrap);
 
+                        if (++index < previousLineBreak.RemainingCharacters.Count)
+                        {
+                            for (; index < previousLineBreak.RemainingCharacters.Count; index++)
+                            {
+                                splitResult.Second.Add(previousLineBreak.RemainingCharacters[index]);
+                            }
+                        }
+
                         nextLineBreak = new TextLineBreak(splitResult.Second);
 
                         return splitResult.First;
@@ -323,9 +334,10 @@ namespace Avalonia.Media.TextFormatting
         /// <param name="textRange">The text range that is covered by the text runs.</param>
         /// <param name="paragraphWidth">The paragraph width.</param>
         /// <param name="paragraphProperties">The text paragraph properties.</param>
+        /// <param name="currentLineBreak">The current line break if the line was explicitly broken.</param>
         /// <returns>The wrapped text line.</returns>
-        private static TextLine PerformTextWrapping(IReadOnlyList<ShapedTextCharacters> textRuns, TextRange textRange,
-            double paragraphWidth, TextParagraphProperties paragraphProperties)
+        private static TextLine PerformTextWrapping(List<ShapedTextCharacters> textRuns, TextRange textRange,
+            double paragraphWidth, TextParagraphProperties paragraphProperties, TextLineBreak currentLineBreak)
         {
             var availableWidth = paragraphWidth;
             var currentWidth = 0.0;
@@ -388,8 +400,22 @@ namespace Avalonia.Media.TextFormatting
                     var textLineMetrics = TextLineMetrics.Create(splitResult.First,
                         new TextRange(textRange.Start, currentLength), paragraphWidth, paragraphProperties);
 
-                    var lineBreak = splitResult.Second != null && splitResult.Second.Count > 0 ?
-                        new TextLineBreak(splitResult.Second) :
+                    var remainingCharacters = splitResult.Second;
+
+                    if (currentLineBreak?.RemainingCharacters != null)
+                    {
+                        if (remainingCharacters != null)
+                        {
+                            remainingCharacters.AddRange(currentLineBreak.RemainingCharacters);
+                        }
+                        else
+                        {
+                            remainingCharacters = new List<ShapedTextCharacters>(currentLineBreak.RemainingCharacters);
+                        }
+                    }
+
+                    var lineBreak = remainingCharacters != null && remainingCharacters.Count > 0 ?
+                        new TextLineBreak(remainingCharacters) :
                         null;
 
                     return new TextLineImpl(splitResult.First, textLineMetrics, lineBreak);
@@ -403,7 +429,10 @@ namespace Avalonia.Media.TextFormatting
             }
 
             return new TextLineImpl(textRuns,
-                TextLineMetrics.Create(textRuns, textRange, paragraphWidth, paragraphProperties));
+                TextLineMetrics.Create(textRuns, textRange, paragraphWidth, paragraphProperties),
+                currentLineBreak?.RemainingCharacters != null ?
+                    new TextLineBreak(currentLineBreak.RemainingCharacters) :
+                    null);
         }
 
         /// <summary>
@@ -434,7 +463,7 @@ namespace Avalonia.Media.TextFormatting
 
         internal readonly struct SplitTextRunsResult
         {
-            public SplitTextRunsResult(IReadOnlyList<ShapedTextCharacters> first, IReadOnlyList<ShapedTextCharacters> second)
+            public SplitTextRunsResult(List<ShapedTextCharacters> first, List<ShapedTextCharacters> second)
             {
                 First = first;
 
@@ -447,7 +476,7 @@ namespace Avalonia.Media.TextFormatting
             /// <value>
             /// The first text runs.
             /// </value>
-            public IReadOnlyList<ShapedTextCharacters> First { get; }
+            public List<ShapedTextCharacters> First { get; }
 
             /// <summary>
             /// Gets the second text runs.
@@ -455,7 +484,7 @@ namespace Avalonia.Media.TextFormatting
             /// <value>
             /// The second text runs.
             /// </value>
-            public IReadOnlyList<ShapedTextCharacters> Second { get; }
+            public List<ShapedTextCharacters> Second { get; }
         }
 
         private struct TextRunEnumerator
diff --git a/src/Avalonia.Visuals/Media/TextFormatting/TextLayout.cs b/src/Avalonia.Visuals/Media/TextFormatting/TextLayout.cs
index 14602a2560..fa7d6cb4bf 100644
--- a/src/Avalonia.Visuals/Media/TextFormatting/TextLayout.cs
+++ b/src/Avalonia.Visuals/Media/TextFormatting/TextLayout.cs
@@ -183,7 +183,10 @@ namespace Avalonia.Media.TextFormatting
             var glyphRun = TextShaper.Current.ShapeText(new ReadOnlySlice<char>(s_empty, startingIndex, 1),
                 properties.Typeface, properties.FontRenderingEmSize, properties.CultureInfo);
 
-            var textRuns = new[] { new ShapedTextCharacters(glyphRun, _paragraphProperties.DefaultTextRunProperties) };
+            var textRuns = new List<ShapedTextCharacters>
+            {
+                new ShapedTextCharacters(glyphRun, _paragraphProperties.DefaultTextRunProperties)
+            };
 
             return new TextLineImpl(textRuns,
                 TextLineMetrics.Create(textRuns, new TextRange(startingIndex, 1), MaxWidth, _paragraphProperties));
diff --git a/src/Avalonia.Visuals/Media/TextFormatting/TextLineImpl.cs b/src/Avalonia.Visuals/Media/TextFormatting/TextLineImpl.cs
index 435752160e..8b44e32c48 100644
--- a/src/Avalonia.Visuals/Media/TextFormatting/TextLineImpl.cs
+++ b/src/Avalonia.Visuals/Media/TextFormatting/TextLineImpl.cs
@@ -6,9 +6,9 @@ namespace Avalonia.Media.TextFormatting
 {
     internal class TextLineImpl : TextLine
     {
-        private readonly IReadOnlyList<ShapedTextCharacters> _textRuns;
+        private readonly List<ShapedTextCharacters> _textRuns;
 
-        public TextLineImpl(IReadOnlyList<ShapedTextCharacters> textRuns, TextLineMetrics lineMetrics,
+        public TextLineImpl(List<ShapedTextCharacters> textRuns, TextLineMetrics lineMetrics,
             TextLineBreak lineBreak = null, bool hasCollapsed = false)
         {
             _textRuns = textRuns;
diff --git a/src/Avalonia.Visuals/Rendering/RenderLoop.cs b/src/Avalonia.Visuals/Rendering/RenderLoop.cs
index 789d028a3a..b2a6b0da19 100644
--- a/src/Avalonia.Visuals/Rendering/RenderLoop.cs
+++ b/src/Avalonia.Visuals/Rendering/RenderLoop.cs
@@ -18,6 +18,7 @@ namespace Avalonia.Rendering
     {
         private readonly IDispatcher _dispatcher;
         private List<IRenderLoopTask> _items = new List<IRenderLoopTask>();
+        private List<IRenderLoopTask> _itemsCopy = new List<IRenderLoopTask>();
         private IRenderTimer _timer;
         private int _inTick;
         private int _inUpdate;
@@ -63,11 +64,14 @@ namespace Avalonia.Rendering
             Contract.Requires<ArgumentNullException>(i != null);
             Dispatcher.UIThread.VerifyAccess();
 
-            _items.Add(i);
-
-            if (_items.Count == 1)
+            lock (_items)
             {
-                Timer.Tick += TimerTick;
+                _items.Add(i);
+
+                if (_items.Count == 1)
+                {
+                    Timer.Tick += TimerTick;
+                }
             }
         }
 
@@ -76,12 +80,14 @@ namespace Avalonia.Rendering
         {
             Contract.Requires<ArgumentNullException>(i != null);
             Dispatcher.UIThread.VerifyAccess();
-
-            _items.Remove(i);
-
-            if (_items.Count == 0)
+            lock (_items)
             {
-                Timer.Tick -= TimerTick;
+                _items.Remove(i);
+
+                if (_items.Count == 0)
+                {
+                    Timer.Tick -= TimerTick;
+                }
             }
         }
 
@@ -129,10 +135,20 @@ namespace Avalonia.Rendering
                         }, DispatcherPriority.Render);
                     }
 
-                    for(int i = 0; i < _items.Count; i++)
+                    lock (_items)
+                    {
+                        _itemsCopy.Clear();
+                        foreach (var i in _items)
+                            _itemsCopy.Add(i);
+                    }
+
+                    for (int i = 0; i < _itemsCopy.Count; i++)
                     {
-                        _items[i].Render();
+                        _itemsCopy[i].Render();
                     }
+                    
+                    _itemsCopy.Clear();
+
                 }
                 catch (Exception ex)
                 {
diff --git a/src/Avalonia.Visuals/Rendering/SleepLoopRenderTimer.cs b/src/Avalonia.Visuals/Rendering/SleepLoopRenderTimer.cs
new file mode 100644
index 0000000000..79e029ccd2
--- /dev/null
+++ b/src/Avalonia.Visuals/Rendering/SleepLoopRenderTimer.cs
@@ -0,0 +1,72 @@
+using System;
+using System.Diagnostics;
+using System.Threading;
+
+namespace Avalonia.Rendering
+{
+    public class SleepLoopRenderTimer : IRenderTimer
+    {
+        private Action<TimeSpan> _tick;
+        private int _count;
+        private readonly object _lock = new object();
+        private bool _running;
+        private readonly Stopwatch _st = Stopwatch.StartNew();
+        private readonly TimeSpan _timeBetweenTicks;
+
+        public SleepLoopRenderTimer(int fps)
+        {
+            _timeBetweenTicks = TimeSpan.FromSeconds(1d / fps);
+        }
+        
+        public event Action<TimeSpan> Tick
+        {
+            add
+            {
+                lock (_lock)
+                {
+                    _tick += value;
+                    _count++;
+                    if (_running)
+                        return;
+                    _running = true;
+                    new Thread(LoopProc) { IsBackground = true }.Start();
+                }
+
+            }
+            remove
+            {
+                lock (_lock)
+                {
+                    _tick -= value;
+                    _count--;
+                }
+            }
+        }
+
+        void LoopProc()
+        {
+            var now = _st.Elapsed;
+            var lastTick = now;
+
+            while (true)
+            {
+                var timeTillNextTick = lastTick + _timeBetweenTicks - now;
+                if (timeTillNextTick.TotalMilliseconds > 1) Thread.Sleep(timeTillNextTick);
+
+                lock (_lock)
+                {
+                    if (_count == 0)
+                    {
+                        _running = false;
+                        return;
+                    }
+                }
+
+                _tick?.Invoke(now);
+                now = _st.Elapsed;
+            }
+        }
+
+
+    }
+}
diff --git a/src/Avalonia.X11/X11Platform.cs b/src/Avalonia.X11/X11Platform.cs
index 9e9c4fd30e..7f3255d4da 100644
--- a/src/Avalonia.X11/X11Platform.cs
+++ b/src/Avalonia.X11/X11Platform.cs
@@ -47,7 +47,7 @@ namespace Avalonia.X11
             AvaloniaLocator.CurrentMutable.BindToSelf(this)
                 .Bind<IWindowingPlatform>().ToConstant(this)
                 .Bind<IPlatformThreadingInterface>().ToConstant(new X11PlatformThreading(this))
-                .Bind<IRenderTimer>().ToConstant(new DefaultRenderTimer(60))
+                .Bind<IRenderTimer>().ToConstant(new SleepLoopRenderTimer(60))
                 .Bind<IRenderLoop>().ToConstant(new RenderLoop())
                 .Bind<PlatformHotkeyConfiguration>().ToConstant(new PlatformHotkeyConfiguration(KeyModifiers.Control))
                 .Bind<IKeyboardDevice>().ToFunc(() => KeyboardDevice)
diff --git a/src/Skia/Avalonia.Skia/TextShaperImpl.cs b/src/Skia/Avalonia.Skia/TextShaperImpl.cs
index b0384a1fdf..61075171fe 100644
--- a/src/Skia/Avalonia.Skia/TextShaperImpl.cs
+++ b/src/Skia/Avalonia.Skia/TextShaperImpl.cs
@@ -123,10 +123,7 @@ namespace Avalonia.Skia
                 return;
             }
 
-            if (offsetBuffer == null)
-            {
-                offsetBuffer = new Vector[glyphPositions.Length];
-            }
+            offsetBuffer ??= new Vector[glyphPositions.Length];
 
             var offsetX = position.XOffset * textScale;
 
@@ -138,10 +135,7 @@ namespace Avalonia.Skia
         private static void SetAdvance(ReadOnlySpan<GlyphPosition> glyphPositions, int index, double textScale,
             ref double[] advanceBuffer)
         {
-            if (advanceBuffer == null)
-            {
-                advanceBuffer = new double[glyphPositions.Length];
-            }
+            advanceBuffer ??= new double[glyphPositions.Length];
 
             // Depends on direction of layout
             // advanceBuffer[index] = buffer.GlyphPositions[index].YAdvance * textScale;