On Ubuntu 20.04 sometimes when I get out of sleep I have just a black screen. I might get it also just when I get out of the lockout. The login page does not appear I just have a black screen.
I use 2 screens, the first one is a laptop screen reversed and an external monitor which is the primary one.
So I think that it's a GDM issue. Where to check what bugs? Is there any log file?
