Thank you for your bug report, it seems those session fail to start. Could you try to log in like on your video and once you are back on lightdm do "ctrl-alt-f1", log in as the user which just hit the bug, and copy .xsession-errors somewhere and add it to this bug?
** Changed in: lightdm (Ubuntu) Importance: Undecided => High ** Changed in: lightdm (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/990948 Title: I can start a session with different user To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/990948/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs