I use to tag (in roon) the performers.
2 basic tags i use are ART for artists that do have a big artist picture in roon metadata, and PHOTO for those with a custom big picture i have added. (then many more tags, basically about the main instrument, SAX, GUITAR, and so on).
anyway, looking at the composers page and filtering with the tag i get something like this:
Hi @dylan
no, in the Tags page, when i select ART, i get first all the artists (primary or performer) that have been tagged.
then, after, i get the (very few) composers with the tag.
but, as an aside, if i take an artist who is also a composer and put a doubled tag (on the performer page and on the composer page) i get the artist 2 times.
anyway, the answer to the second question is no.
if it worked in the past, i cannot answer. in fact the ART tag was meant only for the primary artists, where i could have some chance to fill up all the gray boxes in the artists page with decent pictures. this task, in the composers page is simply a no-way…
so i never tried to filter in any way the composers page. till now.
If i go in tags page, and look for a tag (ART in this example) i see that there are 3536 ARTISTS with this tag (note the comma near the number, that’s an error!)
but then i can click in the view menu, and select composers or tracks (it should result in nothing, as i have no tracks or composers tagged with ART).
instead, i get this: