after almost 15yrs my plex server is no more. jellyfin behind nginx with authentik is running very nicely.
not OP, but this has reared its ugly face once or twice with my friends.
i have been running into another issue, though it may be a firefox issue: playing some filetypes fail to play on web browser but work fine on jellyfin app (i believe my settings are correct for hardware decode on server where it can)
i still have to put some time into figuring it out tho (havent really done my research yet)