With a fresh install of 2.13.3 (portable), I turn on Metadata: Use track relationships (this is the only change I make):
I then tag a FLAC audio file with “performer:lead vocals” = Chrosky:
Yet the actual tag becomes “performer” = Chrosky (lead vocals):
Manually editing this tag to “performer:lead vocals” = Chrosky shows no difference when brought back into Picard:
How do I force Picard to write the role to the tag rather than the performer?
it could be as simple as the second program displaying tags differently? what is the second program that shows “Chrosky (lead vocals)”?
That’s how Picard stores roles in Vorbis tags, as PERFORMER=Name (role). There is currently no way to change this.
There is software that interprets and displays “PERFORMER” tags. But do you know a tool that would handle "PERFORMER:ROLE` (actually displa this as performers, and not only just list all tags)?
I’m using the extended tags dialog in Mp3tag. This is what I see after manually editing the tag:
Quod Libet combines roles per person, so when I manually append the roles to the performer tag, the program can interpret the performers like so:
Not to shill Quod Libet or anything…
We could make it an option to store the role after a colon for Vorbis tags (and APE tags as well I guess, as it is handled similarly there). But right now it is not possible to save the tag like this with Picard. If it works with MP3Tag use this to change the performer tags for now.
I see Quod Libet documents the performer tag with the colon in their user guide: An Introduction to Tags — Quod Libet
That difference between Quod Libet and Picard is interesting, as a lot of the tag handling was inspired by Quod Libet.
I never would’ve expected 
I’ll see if I can get a regex script working to save myself the headache
I have “solved” this problem the other way around, by running a customized version of QuodLibet from source which parses the Picard-style performer tags:
The differences between, and limitations of, different tagging formats (ID3, Vorbis etc.) is a PITA. Some tags are not supported at all, some tags (like performer) operate differently. It would be great if there were greater commonality.
There isn’t an industry wide body to coordinate tag formats. Even ID3 (which is pretty well defined and has a lot of tags) is only an informal standard, but other formats have grown organically by one software developer implementing a new tag and others discovering it and following along. It would be great if there was greater coordination.
(Even ID3 has some de-facto changes of use - I can’t remember the details but I have a feeling that some date fields are used differently in Picard and other software than the ID3 standard actually defines.)
It would be great if MusicBrainz were to take a leadership role in creating better coordination because it is one of the few independent open-source organisations with the respect needed to do so.
But even if MusicBrainz doesn’t try to coordinate there is nothing stopping it creating new tags to improve commonality, and hoping that (because MusicBrainz and Picard are major players) these become a de-facto standard.
