Screen splits diagonally in full screen video mode (Netflix, YouTube, etc.)

Hi,

I cannot watch videos on full screen mode either on Netflix, YouTube or some other videos. What happens is that the screen splits diagonally and the left part of the picture gets moved to the right side of the screen.

When I move the mouse, it's normal again but goes back to the split once the mouse stops moving. It's gotten progressively worse over the past few weeks (it only used to happen occasionally). Vimeo seems to be fine, though. Don't know if it's because of an update to MacOS Catalina 10.15.4 or not.

I use Google Chrome but I seem to not be the only one dealing with this. It seems that this thread https://support.google.com/youtube/thread/18513121?hl=en suggests, that this happened after the update to Catalina, even with people who use Safari etc. Found what seemed to be a workaround in this thread: System Preferences > Displays > click "scaled display" and then pick a random resolution rather than "default for display".

For me, however, only the lower displays seem to solve the video split screen problem. Ok for watching but not ok for working, surfing, typing etc. When I click on the highest resolution that matched the "default for display", I get the same issues. When I check "displays" again, it seems the OS switches me back over to "default for display" again and again. It's' quite irritating. Can somebody please help me with a solution to this problem?

Thanks!