Long standing issues

[o-alquimista]

These seem to be related:

1. LightDM has a long standing security issue: https://bugs.launchpad.net/ubuntu/+source/unity/+bug/1532508
2. elementary users are reporting multiple problems related to the greeter: After waking up, the desktop is visible for a short period before OS locks #397, Lock Screen Security #546, Display freezes often #78, Black screen after logging #525, etc.
3. Xorg currently runs as root. GDM, for instance, can run Xorg rootless.

EDIT: the bug report linked on number 1 is not for LightDM. My mistake. However, the security issue exists, and it affects elementary as well as other distributions that use LightDM.