I expose jellyfin to the internet, and some precautions I have taken that I don’t see mentioned in these answers are: 1) run jellyfin as a rootless container, and 2) use read-only storage where ever possible. If you have other tools managing things like subtitles and metadata files before jellyfin there’s no reason for jellyfin to have read access to the media it hosts. While this doesn’t directly address the documented security flaws with jellyfin, you may as well treat it like a diseased plague rat if you’re going to expose it. To me, that means worst case scenario is the thing is breached and the only thing for an attacker to do is exfiltrate things limited to jellyfin.