[iOS/Mac Catalyst 26] Fix NavigationPage content not extending behind floating glass tab bar

src/Controls/src/Core/Compatibility/Handlers/NavigationPage/iOS/NavigationRenderer.cs

@@ -1535,7 +1535,20 @@ public override void ViewWillAppear(bool animated)
 				var isTranslucent = false;
 				if (_navigation.TryGetTarget(out n))
 					isTranslucent = n.NavigationBar.Translucent;
-				EdgesForExtendedLayout = isTranslucent ? UIRectEdge.All : UIRectEdge.None;
+
+				var edges = isTranslucent ? UIRectEdge.All : UIRectEdge.None;
+
+				// On iOS/MacCatalyst 26+, the tab bar renders as a floating glass overlay.
+				// Extend behind it when inside a visible UITabBarController so content
+				// isn't clipped at the old tab bar boundary.
+				if ((OperatingSystem.IsIOSVersionAtLeast(26) || OperatingSystem.IsMacCatalystVersionAtLeast(26))
+					&& TabBarController is { } tbc
+					&& !tbc.TabBar.Hidden)
+				{
+					edges |= UIRectEdge.Bottom;
+				}
+
+				EdgesForExtendedLayout = edges;
 
 				base.ViewWillAppear(animated);
 			}

src/Controls/tests/TestCases.HostApp/Issues/Issue35490.cs

@@ -0,0 +1,41 @@
+using TabbedPage = Microsoft.Maui.Controls.TabbedPage;
+
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 35490, "[iOS 26] TabbedPage with NavigationPage children clips content above floating glass tab bar", PlatformAffected.iOS)]
+public class Issue35490 : TabbedPage
+{
+	public Issue35490()
+	{
+		var page1 = new ContentPage
+		{
+			Title = "Tab1",
+			BackgroundColor = Colors.MediumPurple,
+			Content = new Label
+			{
+				AutomationId = "Tab1Label",
+				Text = "Tab 1 — on iOS 26+, test passes if purple background extends under the floating tab bar",
+				TextColor = Colors.White,
+				VerticalOptions = LayoutOptions.Center,
+				HorizontalOptions = LayoutOptions.Center,
+			},
+		};
+
+		var page2 = new ContentPage
+		{
+			Title = "Tab2",
+			BackgroundColor = Colors.DarkCyan,
+			Content = new Label
+			{
+				AutomationId = "Tab2Label",
+				Text = "Tab 2 — on iOS 26+, test passes if cyan background extends under the floating tab bar",
+				TextColor = Colors.White,
+				VerticalOptions = LayoutOptions.Center,
+				HorizontalOptions = LayoutOptions.Center,
+			},
+		};
+
+		Children.Add(new NavigationPage(page1) { Title = "Tab1" });
+		Children.Add(new NavigationPage(page2) { Title = "Tab2" });
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue35490.cs

@@ -0,0 +1,24 @@
+#if IOS || MACCATALYST // The floating glass tab bar is a UIKit-only feature introduced in iOS/MacCatalyst 26. This issue does not affect Android or Windows.
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue35490 : _IssuesUITest
+{
+	public Issue35490(TestDevice testDevice) : base(testDevice)
+	{
+	}
+
+	public override string Issue => "[iOS 26] TabbedPage with NavigationPage children clips content above floating glass tab bar";
+
+	[Test]
+	[Category(UITestCategories.TabbedPage)]
+	public void NavigationPageChildContentExtendsUnderFloatingTabBar()
+	{
+		App.WaitForElement("Tab1Label");
+		VerifyScreenshot();
+	}
+}
+#endif