I also have encountered this issue.
I’m running a fresh installation of Windows 11 with an Nvidia 4070 graphics card, as well as Unreal Engine versions 5.1 and 5.2.
I have two 2K screens, and the main screen in Unreal Engine frequently goes black. I can temporarily bring it back by pressing Alt+Tab, but as soon as I switch back to Unreal Engine, the screen flickers and goes black again.
I attempted the solution mentioned in the Nvidia support article by modifying the registry, but unfortunately, it didn’t resolve the issue. Here is the link to the article: After updating to NVIDIA Game Ready Driver 461.09 or newer, some desktop apps may flicker or stutter when resizing the window on some PC configurations | NVIDIA
Although the latest Nvidia driver download claims to have fixed the black screen or flickering problem, I am still experiencing this issue.
Tomorrow, I plan to try installing previous versions of the Nvidia drivers to see if that resolves the problem.