Trickplay and Chapter Images storage location.

[Nariagari]

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With the way it is now, you don't have to worry about that. The trickplay files now get deleted by Jellyfin when it detects they're not needed anymore.

This would also be possible if the trickplay is not stored in the config folder.
Jellyfin knows when a file chances, so it can delete the trickplay on rescan and generate a new one afterward. This probably is the current behavior anyway.

Also, if you delete a movie, you'd normally delete the folder and not just the movie file, especially if you store pictures and nfo files in the media location.