This is not a question about preview thumbnails, but rather the thumbs that are used for Extras content (trailers, making-of’s, etc.). In some clients these are displayed on-screen with thumbnails while in others they’re only listed as text. Is there any way to choose a picture to be used as the thumbnail in those clients with a graphical display? My files are almost all mkv’s and I tried including an mkv attachment titled cover.jpg through mkvmerge. That appears to be the closest thing to a standard. But Plex doesn’t seem to care about that and just grabs a random frame from the beginning of the vid. Can this be controlled at all?
Well, not sure about extras BUT if it’s anything like movies/shows then you can name the jpg/png/etc the same name as the extras IF you have the extra on your hard drive.
I just tried adding to a movie folder “Bogus extra-scene.mp4” and Bogus extra-scene.png" and it did not pull the thumbnail from the png file but rather from within the mp4 file. So I would conclude that this approach sadly will not work.
