Full creen apps display a black screen when GSync(-compatible, officially) is active, kernel 5.5, driver 440.64

This bug appeared with kernel 5.5, the driver was fine with 5.4. Games and videos display a fully black screen when I let them go fullscreen. When I use regular a window, it’s ok. I can also switch to virtual workspaces. This only happens when gsync is on(default).

Happens with kernel 5.4 too on ubuntu 20.04, driver: 440.82

It seems like whenever I attach a HDMI cable to my monitor, gsync-compatible breaks - it doesn’t matter that the cable connects to the same PC or some other. This is on 5.4 of course - with 5.5 and later gsync-compatible is still broken.