Hello guys, found it on Reddit, and its really works for me, i dont have any blackscreens anymore.
I finally managed to fix the Alt+Tab issue, run gpedit and go here:
Computer Configuration > Administrative Templates > Windows Components > Windows Update > Manage updates offered from Windows Update>Enable optional updates
First, change the setting from "no configured to "enabled", then you have to choose the first option (Including CFRs) so you instantly get enabled the gradual rollout features after installing the update.
Uninstall the recent updates including KB5044384 and install them again using windows update after the gpedit modification.
Also, make sure you have enabled fullscreen optimizations. If you disable it, forget about the instant Alt+Tab and HDR while exclusive fullscreen.