Wayland dark screen in Wayland session since 50th release kernel 6.8 update when an Nvidia card provided of 550 proprietary driver are applied.
Hi - folks here would likely need some more information to help diagnose, so including your system information from the Info Center app (using the Copy Details button) would be helpful.
However, the general description given reminded me of these bugs: 481950 – Dark screen in wayland with NVIDIA GPU and 489521 – (ICC, Profile) ICC profiles too dark on KDE Wayland Nvidia 555 driver
Do either of those match what you’re experiencing?