[Windows] Fix for FlyoutItem in overflow menu not fully interactable

src/Controls/tests/TestCases.HostApp/Issues/Issue23803.cs

@@ -0,0 +1,40 @@
+namespace Maui.Controls.Sample.Issues
+{
+	[Issue(IssueTracker.Github, 23803, "FlyoutItem in overflow menu not fully interactable", PlatformAffected.UWP)]
+	public partial class Issue23803 : TestShell
+	{
+		protected override void Init()
+		{
+			CreateTabContent();
+		}
+
+		private void CreateTabContent()
+		{
+			var flyoutItem = new FlyoutItem { Title = "Header" };
+			for (int i = 1; i <= 20; i++)
+			{
+				var contentPage = new ContentPage
+				{
+					Content = new Button
+					{
+						Text = $"Button_{i}",
+						AutomationId = $"Button{i}",
+						FontSize = 24,
+						HorizontalOptions = LayoutOptions.Center,
+						VerticalOptions = LayoutOptions.Center
+					}
+				};
+
+				var shellContent = new ShellContent
+				{
+					Title = $"Tab{i}",
+					Content = contentPage
+				};
+
+				flyoutItem.Items.Add(shellContent);
+			}
+			this.FlyoutBehavior = FlyoutBehavior.Disabled;
+			this.Items.Add(flyoutItem);
+		}
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue23803.cs

@@ -0,0 +1,31 @@
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues
+{
+	public class Issue23803 : _IssuesUITest
+	{
+		public override string Issue => "FlyoutItem in overflow menu not fully interactable";
+
+		public Issue23803(TestDevice device)
+		: base(device)
+		{ }
+
+		[Test]
+		[Category(UITestCategories.Shell)]
+		public void VerifyClickAroundOverflowMenuItem()
+		{
+			App.Tap("More");
+#if WINDOWS			
+			var rect = App.WaitForElement("Tab18").GetRect();
+			App.TapCoordinates(rect.X + 80, rect.Y + 15);
+			App.WaitForElement("Button18");
+#else
+			App.WaitForElement("Tab6");
+			App.Tap("Tab6");
+			App.WaitForElement("Button6");
+#endif
+		}
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/XFIssue/Issue6784.cs

@@ -1,5 +1,3 @@
-#if TEST_FAILS_ON_WINDOWS // When using App.Tap to interact with tab items which placed in the more section, the action targets the corner of the tabs, Line No 24
-// which doesn't trigger navigation on Windows. Windows requires tapping directly on the tab title text.
 using NUnit.Framework;
 using UITest.Appium;
 using UITest.Core;
@@ -61,4 +59,3 @@ public void TwoMoreControllerDoesNotShowEditButton()
 #endif
 	}
 }
-#endif

src/Core/src/Platform/Windows/NavigationViewItemViewModel.cs

@@ -4,6 +4,7 @@
 using System.ComponentModel;
 using System.Runtime.CompilerServices;
 using Microsoft.UI.Xaml.Controls;
+using Microsoft.UI.Xaml.Media;
 using WBrush = Microsoft.UI.Xaml.Media.Brush;
 using WIconElement = Microsoft.UI.Xaml.Controls.IconElement;
 
@@ -110,7 +111,7 @@ public WBrush? Foreground
 
 		public WBrush? Background
 		{
-			get => IsSelected ? SelectedBackground : UnselectedBackground;
+			get => (IsSelected ? SelectedBackground : UnselectedBackground) ?? new SolidColorBrush(Microsoft.UI.Colors.Transparent); //The Background color is set to null since both SelectedBackground and UnselectedBackground return null. Adding a default transparent background ensures it is never null, preventing rendering inconsistencies.
 		}
 
 		public object? Data