It seems to me that choosing "lightdm" is more accurate for a starting point based on the lightdm log.
** Package changed: xfce4-taskmanager (Ubuntu) => lightdm (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1229450 Title: Disabling superfluous "Laptop" display output hangs reboot somewhere(?) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1229450/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs