I have an interesting and annoying bug which seems to have recently occured since upgrading to Windows 11.
When viewing Premiere Pro in fullscreen on my 4K display (175% DPI scaling) the timeline and right-hand panel does not update. It's like the window is not bothering to repaint itself for any events. Not only this, but clicking on the Pr icon in the task bar does nothing - it doesn't minimise the application like it usually does, and in fact prevents you from selecting any other windows in this way too. The only way to see any other windows is to minimise Premiere Pro.
I spent some time trying to bug fix this (reinstalling, updating graphics, resetting preferences, clearing caches) until I realised that if I make the window not fullscreen, and the window is at least several pixels smaller than the available area on both the width and height (excluding the taskbar) then the window DOES repaint. (Note that if I just drag the window to be as big as it can be on screen it still malfunctions).
Whilst this bug is exhibiting it is also consuming 25% continuously of an 8 core CPU.