Jewel case thumbnail question

Is it possible to display a jewel case thumbnail using an album's embedded album art only? Or does the folder have to contain the coverart.jpg file? Below is how my folders look with embedded album art (added using Mp3tag).

It has to be folder.jpg or coverart.jpg (or whatever coverart.jpg is renamed to in the advanced prefs, if you choose to do that).

Cheers Leo. I'll batch extract the album art using Mp3tag as I really like this jewel case thumbnail feature. (I only discovered this today incidentally; one of the many joys of using Opus.)