[MULTISCREEN] FPS keeps falling and falling the longer your session lasts

I've finally isolated that the issue is somehow related to having two active screens.

The issue began on 7th of January (Steam client) and hasn't been fixed since. You can "reset" the situation by clearing the cache, but this doesn't seem to occur if you're playing only one display on.

Game is running on 4k display (windowed full screen) and on the side there's a 1440p display (for market).

RTX 4080, latest drivers, Win 11 Pro with latest drivers.