Comment 2 for bug 862802

Confirmed, reproduced on a virtual machine.

- It's not necessary to use Unity2d when logging back in, this happens even if you just log out and back in with Unity 3d.

- The checkbox frontend dies, but it leaves behind the .cache/checkbox/lock file and the sudo-privileged backend. This means that checkbox had no time to clean up or send the stop message to the backend, which in turn suggests that whichever signal gets sent to checkbox when logging out is not being handled correctly, if it gets sent at all.

- Looking at the log file, there are no errors or indications that checkbox was aware it got shut down. As far as checkbox knew, it was waiting for user input when it got killed, with no chance to clean up or log anything.

I'm setting as medium since, even though it's an unlikely use case, it's pretty nasty because it's not obvious how to get checkbox to a running state again (remove .cache/checkbox and either kill the backend manually or reboot so it disappears).