SOLVED: Jellyfin doesn't work

[TheDreadPirate]

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With the above in mind, would there be a way to move the data folder to a more sensible place? If so, which one would you recommend?

Maybe make a folder in / called "library" or something?  Owned by you, group owned by jellyfin, 770.  Or 750 if you don't plan to save NFOs or have the jellyscrub plugin.

Move all your media into that folder. If you are using FTP with your credentials, then your FTP client shouldn't have any issues writing in that directory.

Not that I recall, no. How would I go about changing the data directory back to /var/lib/jellyfin?

Unless someone chimes in, I will have to get back to you when I get home from work in about 4 hours to work out the steps.