Jellyfin upgrade issue

[TheDreadPirate]

You could relocate those directories to a temp folder then reinstall Jellyfin to simulate a "fresh install". Access the fresh install from a private or incognito browser to verify that it is a "working" fresh install. Then you would stop Jellyfin, restore those directories, then start jellyfin.

Try accessing Jellyfin again and it should be like nothing happened. I've had to do this process a once (before I switched to Docker) and it was as simple as it sounds.