Comment 8 for bug 1563048

I have the same issue - upgraded from 15.10 to 16.04 (Kubuntu) and the login screen, after entering username/password, does nothing. Changing to the console and back seems to go straight to the desktop if you have left it long enough, which suggests the logging in is continuing and the greeter thing is just stuck or something?

I definitely have xserver-xorg-core installed.