I was having the same issues as the other folks. The fixes in the above posts fixed the issues.
In Nextcloud docker cli enter: occ app:disable documentserver_community
In Unraid cli enter: docker exec -it nextcloud updater.phar
Updating from the Unraid cli seems like the way to go!
Thank you!
I just tested port forwarding/adding firewall rule for 4443 and it worked for me too. Previous to that I could get users in the chat but video didn't work for anyone.