Before the upgrade I was using gnome on Ubuntu 16.04 with lightdm and it worked fine. After upgrading to Ubuntu 18.04 I switched to gnome gdm3. On the first day I could login to my user account, configure gnome and so on. However on the next day when I tried to login for the first time, the login screen just comes back again and when I try it for a second time it just freezes. Can someone help me with this problem?
In advance thanks for help.
UPDATE: I switched back to lightdm and it works just fine. However I would still like to use gdm3 because I like it more. How could I do this?