After the 3.5.5 update I faced with several issues as darken screen when mouse move or LMB/RMB press in some games (gamemode), screen color settings don’t work.

Darken screen shows up not in all of games but both steam library and 3rd party games or software added to the library. I am not sure but seems to be it shows up only for the games setet up as windowed. Also all scaling steam features darken the screen. I believe this problem is directly related to the new color settings, as the screen doesn’t just darken, but the colors become richer, as if-the color settings are sometimes broken through. But at the same time in the settings screen itself the sliders have no effect on anything.

I had the vibrant deck plugin before the update, I’ve tried turning it off, uninstalling it, putting it back on, nothing changes, its settings don’t work either. I’ve tried switching to beta and early branches but that didn’t help either.

Has anyone else run into something like this? Internet search didn’t turn up anything.
Any advice is welcome except factory reset, as it will kill 1tb of installed games, including many that were installed and customized separately from steam, like games from gog or emulators.