I have already checked through the existing feature requests and found no duplicates

• Yes

Is this a server-specific feature?

Navidrome

What do you want to be added?

For parity with the Navidrome web UI, add back the separators found in the ARTIST tag while retaining the multi artist functionality provided by the multi valued ARTISTS tag. This means a track feature can be shown with ft., or feat., or a collaborated album can keep its stylized separators such as / or literally anything else.
Same applies to ALBUMARTIST(S).

Examples below:

I also noticed that only the first ALBUMARTISTS is displayed in Feishin, that might be another bug?