Hello. I am trying to open two WPF windows (of the same type) and make them use different themes, to see them live and side by side - this way it's easier to spot style differences. Because applying/comparing themes in design time is not very convenient. I don't really care about style of the window itself, i will be happy to load dark and light style for content.

I can't find a way that, however. My observations:

• SetWindowThemeWpf in window constructor, after InitializeComponent, does nothing visible
• I can omit it entirely and rely only on SetCurrentProcessTheme
• Calling SetWindowThemeWpf as it's suggested in docs, later, eg with a button click, does nothing
• Calling SetCurrentProcessTheme anytime changes the theme for all windows