[TorpX]

I have had to for specific reasons, ALT + TAB while submerged, and (knock on wood) haven't had it happen. Also had to save a couple times while submerged, and come back to the game later on, and had no ill effects, so it could just be a glitch from computer to computer, and not a standard issue that everyone sees.

I have never had the O2 bug, though I haven't Alt-tabbed very much.