I host a few community servers and when I login as Admin or peers as Game Master we discovered that our players randomly disappear from view until we rejoin the game. Their circle indicator does not show in the object panel, we cannot hear them, nor do they appear in the game outside of GM. If we as GMs leave the game and rejoin we can see everyone again with the same roles. It seems like other community members report the same issue.
To help troubleshoot, I tweaked my rendering settings for the JSON to lower and raise the "fog of war" distance views to see if that is the issue. But none of that seemed to help.
I'm still testing to see if the problem happens more often when we place more objects and AI elements into the game scenario. But as of right now it seems completely random.
Also, for note, it seems to happen if the server is modded or not.