I think we can initialize the current modes in win32u as well instead of doing it in explorer.exe.
This is done already, or at least, registry settings is initialized from current settings if it was not set yet. There's a difference though that explorer does this every time it is started while win32u currently only does the first time the cache is initialized.
Exposing these detached sources produces the following errors when using virtual desktop.
But then, I don't see these? I've included a change to explorer to only change display settings for attached devices instead.