DefaultTitleBarShouldMatchAppModeTheme does not respect RequestedTheme

[lolametro]

Describe the bug

AppWindow.DefaultTitleBarShouldMatchAppModeTheme does not respect the Application.RequestedTheme (or ((FrameworkElement)XamlRoot.Content).RequestedTheme) settings.
The title bar color would then still not match the actual theme used in the app.

Steps to reproduce the bug

1. Switch Windows app mode theme to "Dark"
2. Set AppWindow.DefaultTitleBarShouldMatchAppModeTheme = true in the MainWindow
3. Set RequestedTheme = ApplicationTheme.Light in the App ctor OR ((FrameworkElement)Content.XamlRoot.Content).RequestedTheme = ElementTheme.Light in the MainWindow
4. Start the app
5. See a dark title bar, while the app is in light mode

Expected behavior

See a light title bar, while the app is in light mode

Screenshots

NuGet package version

WinUI 3 - Windows App SDK 1.6 Experimental 1: 1.6.240531000-experimental1

Windows version

Windows 11 (22H2): Build 22621

Additional context

This means it is not possible to dynamically switch the title bar color, based on the selection of the user in the app. Most apps offer this kind of setting (even Microsoft apps like Paint), meaning the DefaultTitleBarShouldMatchAppModeTheme will not fit their needs and still require custom code. An additional annoyance is, that RequestedTheme cannot be set at runtime, only in the App ctor (#4474).

[github-actions]

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Please view the issues below to see if they solve your problem, and if the issue describes your problem please consider closing this one. Thank you!

Closed similar issues:

• Changing the theme on runtime while no backdrop is set, will not apply the correct colors (#8249), similarity score: 0.80
• [WinUI 3] Changing the theme of the NavigationView doesn't work as expected (#6938), similarity score: 0.77
• Xaml island: Setting "RequestedTheme" results in broken theming and unreadable text when value differs from system-wide setting (#3576), similarity score: 0.77
• Window titlebar controls do not respect users' theme and settings (#9166), similarity score: 0.76
• RequestedTheme changes are not applied properly to StackPanel and ContentDialog in WinUI 3 Desktop (#5788), similarity score: 0.76

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[ghost1372]

@codendone i tested with v1.6-exp2 and it seems that this issue fixed. so i think this issue can be closed

[lolametro]

@ghost1372 I tested as well with v1.6-exp2, and it's not fixed for me.