I have Fedora 30 Cinnamon. Yesterday I updated the operating system.
I restart my computer and when I tried to log in with my user, my computer screen turned completely black for a second and it didn’t allow me to log in.
I reinstall the graphical environment (Cinnamon) and I try to log in with another user (I create a new user), but the problem persists.
Try to log in with “Cinnamon (Software Rendering)” session type.
I’ve already tried that option and it doesn’t work either.
Try to boot and test the previous kernel.
Also check the DNF history to identify the packages affected by the latest upgrade transaction.
Especially note everything related to Cinnamon, Wayland and video drivers.
Then downgrade those packages and lock their versions.
You can do it either in a text VT or using chroot.