I experienced this problem on Ubuntu 14.10 with Gnome 3.12.2 when I upgraded from the Ubuntu packaged version of gnome to the gnome3-team version. Two other issues arose as well: gnome-terminal its lost profile settings and crashed when I tried to edit them, and the gdm login screen did not display any usernames. Maybe the dconf settings have become inconsistent across the two sources of gnome packages.
Comment #23 (resetting dconf) solved my problem. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1236749 Title: Gnome shell extensions disabled at every startup To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-gnome/+bug/1236749/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs