Comment 8 for bug 1714886

Well i didnt think of that, so I tried it, too. When I turn off my Display that is connected via Displayport, the Gnomeshell is killed after turning the Screen on again. After turning on the Screen the login-window can be seen.
When you log in, its a new Session.
That would explain why in Bug #1718671 the session is only crashing after when you want to unlock the Screen, because the Display was turned off after locking the screen.