Frame should throw on page exceptions

src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml_Controls/Given_Frame.cs

@@ -437,6 +437,58 @@ public void When_NavigatingBetweenPages()
 		Assert.IsTrue(_navigateOrderTracker.FrameNavigated);
 	}
 
+	[TestMethod]
+	public async Task When_Exception_In_Page_Ctor()
+	{
+		var SUT = new Frame()
+		{
+			Width = 200,
+			Height = 200
+		};
+
+#if HAS_UNO
+		bool navigationFailed = false;
+		SUT.NavigationFailed += (s, e) => navigationFailed = true;
+#endif
+
+		TestServices.WindowHelper.WindowContent = SUT;
+		await TestServices.WindowHelper.WaitForLoaded(SUT);
+
+		var exception = Assert.ThrowsException<NotSupportedException>(() => SUT.Navigate(typeof(ExceptionInCtorPage)));
+		Assert.AreEqual("Crashed", exception.Message);
+#if HAS_UNO
+		if (FeatureConfiguration.Frame.UseWinUIBehavior)
+		{
+			// This is only valid with WinUI Frame behavior
+			Assert.IsFalse(navigationFailed);
+		}
+#endif
+	}
+
+	[TestMethod]
+	public async Task When_Exception_In_OnNavigatedTo()
+	{
+		var SUT = new Frame()
+		{
+			Width = 200,
+			Height = 200
+		};
+
+		bool navigationFailed = false;
+		SUT.NavigationFailed += (s, e) =>
+		{
+			navigationFailed = true;
+			e.Handled = true;
+		};
+
+		TestServices.WindowHelper.WindowContent = SUT;
+		await TestServices.WindowHelper.WaitForLoaded(SUT);
+
+		var exception = Assert.ThrowsException<NotSupportedException>(() => SUT.Navigate(typeof(ExceptionInOnNavigatedToPage)));
+		Assert.AreEqual("Crashed", exception.Message);
+		Assert.IsTrue(navigationFailed);
+	}
+
 	[TestCleanup]
 	public void Cleanup()
 	{
@@ -613,3 +665,28 @@ private async void FrameNavigateFirstPage_Loaded(object sender, Microsoft.UI.Xam
 public partial class FrameNavigateSecondPage : Page
 {
 }
+
+public partial class ExceptionInCtorPage : Page
+{
+	public ExceptionInCtorPage()
+	{
+		throw new NotSupportedException("Crashed");
+	}
+}
+
+public partial class ExceptionInOnNavigatedToPage : Page
+{
+	public ExceptionInOnNavigatedToPage()
+	{
+	}
+
+	protected
+#if HAS_UNO
+	internal
+#endif
+	override void OnNavigatedTo(NavigationEventArgs e)
+	{
+		base.OnNavigatedTo(e);
+		throw new NotSupportedException("Crashed");
+	}
+}

src/Uno.UI/UI/Xaml/Controls/Frame/Frame.legacy.cs

@@ -153,7 +153,7 @@ private bool InnerNavigate(PageStackEntry entry, NavigationMode mode)
 				Application.Current.RaiseRecoverableUnhandledException(new InvalidOperationException("Navigation failed", exception));
 			}
 
-			return false;
+			throw;
 		}
 		finally
 		{

src/Uno.UI/UI/Xaml/Controls/Frame/Frame.partial.mux.cs

@@ -301,6 +301,7 @@ private bool NavigateWithTransitionInfoImpl(Type sourcePageType, object paramete
 			catch
 			{
 				pCanNavigate = false;
+				throw;
 			}
 		Cleanup:
 			;
@@ -585,6 +586,8 @@ private void ChangeContent(object oldObject, object newObject, object parameter,
 			{
 				Content = oldObject;
 			}
+
+			throw;
 		}
 	}