[Android] LaunchMode.SingleTask in MainActivity causes blank UI on relaunch (Uno 5.4 regression)

[mikernet]

Current behavior

Starting with 5.4.x, when MainActivity is set to LaunchMode.SingleTask, the app shows a blank UI if it is running persistently in the background (i.e. because it is receiving background location updates) and it is closed/swiped away and then relaunched:

Screen_Recording_20240927_134515_Volt.mp4

Expected behavior

Same as version <= 5.3.x - app UI should restore to its previous state and show properly again after relaunch:

Screen_Recording_20240927_133913_Volt.mp4

How to reproduce it (as minimally and precisely as possible)

[Activity(
    MainLauncher = true,
    LaunchMode = LaunchMode.SingleTask,
    ...)]
public class MainActivity : Microsoft.UI.Xaml.ApplicationActivity

Then run something that will keep the activity alive like a background service or background location updates, swipe away the app, then click the icon to launch it again and reactivate the activity and notice you get a blank screen.

Repro project would require large amounts of actual app code that contains all the permission request logic/UI, background location update service, etc...so if you want that then I will need to send the code privately as I can't share it publicly.

Workaround

None

Works on UWP/WinUI

None

Environment

No response

NuGet package version(s)

5.4.5, 5.5.0-dev-66

Affected platforms

Android

IDE

No response

IDE version

No response

Relevant plugins

No response

Anything else we need to know?

No response