Where does Jellyfin really store collection metadata

[bigggtuna]

I recently organized my library with sonarr and radarr, but with the renaming I obviously lost the organization of my collections due to the filename changes. I wrote a script to help me rewrite the collection.xml files from a backup, but when I replace the collection.xml file at /config/data/collections/collection [boxset]/collection.xml, nothing changes with the collection on Jellyfin. Refreshing metadata on the collection yields nothing. However, when I then add a new item to the collection, the server overwrites the CollectionItems section of the collection.xml while keeping around the rest of the original metadata such as Genres and Studios.

The server must persist the collection mappings somewhere else and only write to (not read from) config/.../collection.xml because if I then overwrite the collection.xml again and add another new item, it overwrites collection.xml again with the first item still in the collection plus the new item. This is a relatively recent change because I have updated my collections once before by replacing all the XML files.

I am running in docker on Unraid, so I have access to the config directory even when the container is off. I tried swapping the XML files while the container was off and starting it up with the new XMLs and none of the collections updated.

And before you ask, yes I am 100% sure I am providing a correct path and XML tags and the file is encoded in utf-8.

Thanks for your help.