fallen phoenix
When interacting with the storage cache at outposts on certain angles and going into the customisation screen of the sights to change the reticule style, you will just. fall out of the map upon entering the customisation menu.
For me, the screen went black and I heard splashing noises as is typical of falling out of the map (I know this because I play on Medved a lot), no popup showed to respawn and entering the escape menu, map, etc. did nothing. I waited about 45 seconds to a minute before I alt f4'd - apparently it respawns you after a while but I didn't wait long enough. Testing at other maps and outposts currently, the video was on Medved at the Vetrenyye Plains Southern Outpost.