Let’s start with C, yes, yes they have and further complicated by which version of Ubuntu did you load and hopefully figured out how not to use the snap version or docker.
If you want to have a stable server I would use use Ubuntu 22.04 and Plex version 1.32.8.7639 and wait for the dust to settle sometime next year.
Release notes: Plex Media Server - #607 by gbooker02
