where where
where where
I don't know why every scrollviewer in your app doesn't support touch. (Maybe you can move to Windows App SDK. That's real WinUI and fully support touch... (And why you...
Yep 
There is a style for separator in SettingExpander.xaml
So this pull is outdated? Would I close it?
Why use .netcore? Useing .netfx will be smaller and don't need to install runtime. And some of nugets which this project used is not support .netcore yet.
It's not much difference between netfx and netcoreapp. You can just change .net6.0 to .net4.8. Because Windows doesn't per-install netcoreapp runtimes. It's very annoying to install them one by one...
I have no idea... It seems that the Thumb can't be moved by touch... Maybe you can try to make it move first... (I don't like WPF. Mybe you can...
This is what I use. https://github.com/Paving-Base/APK-Installer-Classic/blob/main/APKInstaller/APKInstaller/Pages/SettingsPages/TestPage.xaml.cs#L127-L152
...... You need set background by yourself when the backdrop is none...
Maybe you can add modern wpf source into this project, so that you can directly debug it without guess...