This morning I ran sudo apt-get upgrade
and it prompted me to update gnome-shell
. I never really use the gnome desktop environment, but I figured I might as well keep it up-to-date.
After restarting my laptop I noticed that lightdm had selected gnome as the desktop environment and when I tried to switch it back to unity I noticed that unity was missing from the list.
Unity is still installed somewhere, but it seems to have been removed from /usr/share/xsessions/
. I've tried running sudo apt-get install --reinstall unity
, but it doesn't seem to have changed anything.
I've checked this answer here and it suggests that the solution is to remove gnome-shell. I'm a bit hesitant to do this though, if I remove gnome-shell and unity doesn't come back I'll be left without any desktop environment.
sudo apt-get --reinstall install gnome-session
. – vinrav Dec 01 '14 at 13:48