I installed Ubuntu GNOME 15.10 (GNOME 3.16). Things seemed fine but out of nowhere the session froze and left me no other choice but to cold reboot. After reboot, I can't login any more. I type my password, the screen goes black for a second and then returns to the login screen again.
Trying to start gnome-shell from command-line gives an error.
(mutter:1857) Clutter - CRITICAL**. Unable to initialize Clutter: Unable to open display. You have to set the display environment variable, or use the --display argument.
When I specify the display with gnome-shell --display, it always returns an error unable to open display. I already tried a bunch of fixes after Googling, namely removing Xauthority, changing Xauthority permissions, export display, and others I can't remember, but nothing worked whatsoever. Reinstalled gnome-shell, mutter and gdm, still the same issue.
I'm using a laptop with AMD A8-7100 CPU and R7 M265 graphics with the open-source driver.
