diff --git a/src/Avalonia.Base/EnumExtensions.cs b/src/Avalonia.Base/EnumExtensions.cs
new file mode 100644
index 0000000000..a8306c2d69
--- /dev/null
+++ b/src/Avalonia.Base/EnumExtensions.cs
@@ -0,0 +1,23 @@
+// Copyright (c) The Avalonia Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
+using System;
+using System.Runtime.CompilerServices;
+
+namespace Avalonia
+{
+    /// <summary>
+    /// Provides extension methods for enums.
+    /// </summary>
+    public static class EnumExtensions
+    {
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static unsafe bool HasFlagCustom<T>(this T value, T flag) where T : unmanaged, Enum
+        {
+            var intValue = *(int*)&value;
+            var intFlag = *(int*)&flag;
+
+            return (intValue & intFlag) == intFlag;
+        }
+    }
+}
diff --git a/src/Avalonia.Input/PointerPoint.cs b/src/Avalonia.Input/PointerPoint.cs
index e9f3c02b7f..1068a0d4d4 100644
--- a/src/Avalonia.Input/PointerPoint.cs
+++ b/src/Avalonia.Input/PointerPoint.cs
@@ -1,3 +1,6 @@
+// Copyright (c) The Avalonia Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
 namespace Avalonia.Input
 {
     public sealed class PointerPoint
@@ -27,9 +30,9 @@ namespace Avalonia.Input
         public PointerPointProperties(RawInputModifiers modifiers, PointerUpdateKind kind)
         {
             PointerUpdateKind = kind;
-            IsLeftButtonPressed = modifiers.HasFlag(RawInputModifiers.LeftMouseButton);
-            IsMiddleButtonPressed = modifiers.HasFlag(RawInputModifiers.MiddleMouseButton);
-            IsRightButtonPressed = modifiers.HasFlag(RawInputModifiers.RightMouseButton);
+            IsLeftButtonPressed = modifiers.HasFlagCustom(RawInputModifiers.LeftMouseButton);
+            IsMiddleButtonPressed = modifiers.HasFlagCustom(RawInputModifiers.MiddleMouseButton);
+            IsRightButtonPressed = modifiers.HasFlagCustom(RawInputModifiers.RightMouseButton);
 
             // The underlying input source might be reporting the previous state,
             // so make sure that we reflect the current state
diff --git a/src/Windows/Avalonia.Win32/WindowImpl.cs b/src/Windows/Avalonia.Win32/WindowImpl.cs
index 3777ce5e1e..2ae200a179 100644
--- a/src/Windows/Avalonia.Win32/WindowImpl.cs
+++ b/src/Windows/Avalonia.Win32/WindowImpl.cs
@@ -650,9 +650,9 @@ namespace Avalonia.Win32
                         {
                             Input?.Invoke(new RawTouchEventArgs(_touchDevice, touchInput.Time,
                                 _owner,
-                                touchInput.Flags.HasFlag(TouchInputFlags.TOUCHEVENTF_UP) ?
+                                touchInput.Flags.HasFlagCustom(TouchInputFlags.TOUCHEVENTF_UP) ?
                                     RawPointerEventType.TouchEnd :
-                                    touchInput.Flags.HasFlag(TouchInputFlags.TOUCHEVENTF_DOWN) ?
+                                    touchInput.Flags.HasFlagCustom(TouchInputFlags.TOUCHEVENTF_DOWN) ?
                                         RawPointerEventType.TouchBegin :
                                         RawPointerEventType.TouchUpdate,
                                 PointToClient(new PixelPoint(touchInput.X / 100, touchInput.Y / 100)),
@@ -772,11 +772,11 @@ namespace Avalonia.Win32
         {
             var keys = (UnmanagedMethods.ModifierKeys)ToInt32(wParam);
             var modifiers = WindowsKeyboardDevice.Instance.Modifiers;
-            if (keys.HasFlag(UnmanagedMethods.ModifierKeys.MK_LBUTTON))
+            if (keys.HasFlagCustom(UnmanagedMethods.ModifierKeys.MK_LBUTTON))
                 modifiers |= RawInputModifiers.LeftMouseButton;
-            if (keys.HasFlag(UnmanagedMethods.ModifierKeys.MK_RBUTTON))
+            if (keys.HasFlagCustom(UnmanagedMethods.ModifierKeys.MK_RBUTTON))
                 modifiers |= RawInputModifiers.RightMouseButton;
-            if (keys.HasFlag(UnmanagedMethods.ModifierKeys.MK_MBUTTON))
+            if (keys.HasFlagCustom(UnmanagedMethods.ModifierKeys.MK_MBUTTON))
                 modifiers |= RawInputModifiers.MiddleMouseButton;
             return modifiers;
         }
@@ -786,7 +786,7 @@ namespace Avalonia.Win32
             // Ensure that the delegate doesn't get garbage collected by storing it as a field.
             _wndProcDelegate = new UnmanagedMethods.WndProc(WndProc);
 
-            _className = "Avalonia-" + Guid.NewGuid();
+            _className = $"Avalonia-{Guid.NewGuid().ToString()}";
 
             UnmanagedMethods.WNDCLASSEX wndClassEx = new UnmanagedMethods.WNDCLASSEX
             {