Signifying an audience in an object (PieFed/Lemmy)

Hi @andrew_s@piefed.social/@freamon and @nutomic@lemmy.ml —I'm working (not-so-secretly) on refactoring NodeBB so that it is able to "browse" remote audiences/group actors, and that would include things like PieFed and Lemmy communities.

N.B. Given varied nomenclature (group/category/community/subforum), the ForumWG calls this structure an "audience".

Where I am at now is working through the logic for slotting an object into a category.

The most obvious choice here would be to look at as:audience. It's even specified in 1b12, and the majority of threaded implementations follow 1b12.

I am making this post because nutomic explicitly removed the audience from being served in Lemmy (as of January this year), so I don't think relying on that property would be wise.

I asked in that issue whether Lemmy finds community via to/cc (it does). Does PieFed do the same?

Would this also open up the possibility of a topic/context being part of multiple audiences/communities? Interesting...