Backtrace attached.
snifer@snifer-laptop:~$ dpkg -l | grep gdm ii gdm 2.20.4-0ubuntu2 GNOME Display Manager ii gdm-dbgsym 2.20.4-0ubuntu2 debug symbols for package gdm ii ubuntu-gdm-themes 0.26 Ubuntu GDM themes
Backtrace attached.
snifer@ snifer- laptop: ~$ dpkg -l | grep gdm
ii gdm 2.20.4-0ubuntu2 GNOME Display Manager
ii gdm-dbgsym 2.20.4-0ubuntu2 debug symbols for package gdm
ii ubuntu-gdm-themes 0.26 Ubuntu GDM themes