This affects 1.16.200, not 40, but your affected versions list is out of date.

I was playing on my dedicated server when I went through a nether portal back to the overworld and the game wouldn't load. I tried reconnecting on Windows 10 and the game wouldn't load again and clicking cancel did nothing. Same thing happened on Android. The dedicated server logs show "player connected" when I tried to connect, "player disconnected" when I closed Minecraft. Restarting the server fixed this. I never experienced this on 1.16's earlier versions, and I haven't been able to replicate this. Maybe it's bad luck, maybe it will crop up later. I'll comment on this if it happens again, I have a feeling it will.