DataGridRowGroupHeader background and theme changes

[thiago-cs]

The DataGridRowGroupHeader background brush does not respond to app theme changes.
The easiest way to reproduce this is by launching the WindowsCommunityToolkit app, navigate to the DataGrid section, click the "Group by" button. Switch to Windows Settings and switch the system theme. When you go back to the WindowsCommunityToolkit app, you notice the mentioned brush has not updated.
It is not that specific app.

Hello thiago-cs, thank you for opening an issue with us!

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[thiago-cs]

Actually, it is even easier to just use the theme switcher right in the app: simpler and same results.

[michael-hawker]

Thanks for the report @thiago-cs, it is useful to stick to our template though for longevity of the history of the problem.

Seems like we're probably using a StaticResource somewhere instead of a ThemeResource. I'd assume this would be in the controls resources vs. something we're doing for the sample app example specifically.

Think you want to take a stab at fixing it for the community?

FYI @anawishnoff @RBrid

[thiago-cs]

Fixed and submitted PR #4138.