If I start VLC, then plug my laptop into an external monitor via VGA or HDMI, VLC exits normally.
If I then start VLC again, and unplug my laptop from the display, VLC again exits normally.
Probably, this is intended / known behaviour, and my guess is for performance reasons: We need to cache all of X from GPU into immediate RAM while we initialise the new display device but to minimise the risk of X and its children crashing horribly, VLC will be killed rather than preserved.
Is this a correct analysis? What causes VLC to exit?