Couple of Questions (restoring backup, reverse proxy)

[TheDreadPirate]

You cannot simply copy and paste Jellyfin files between different install types. The Jellyfin database contains a lot of absolute paths for metadata and other files that would break when switching from Windows to Linux. Even going from a direct Linux install to a docker install requires some extra work to be able to migrate.

A community member wrote a migration script to make these database changes for migrating from Windows to Docker, but it hasn't been updated in 2 years. So it is possible it no longer works with Jellyfin 10.9 and newer. Worth a try though. Just make sure you have a backup copy.

https://jellyfin.org/docs/general/admini...-migration
https://github.com/MMMZZZZ/Jellyfin-Migrator

If you were restoring from Docker to Docker, you would simply restore the /config and /cache folders you specified in the Docker compose.