FWIW the #ActivityPub protocol seems to embrace things like groups, specifically saying that an entity in the system doesn't have to be an individual. So the underlying technology is already ready for groups.
I'd say the bigger issue is one of UI, how to display groups in a way that users will understand that they're engaging with a group, and how to avoid things like the notorious accidental reply-all in email.
That's a tricky problem to solve, so I hope it's solved sooner rather than later, then clients can move forward implementing the functionality in a better way.
I think that might be regarded as a feature :)
Or, at least, it was left as a higher layer of the system, with AP just concerning itself with moving content around.
It's the same as AP not specifying how one gets an account on Mastodon or how hashtags or display algorithms are to function.
On the up side, like I said above I haven't seen a really good solution to the UI issues if integrating groups here, so at least AP didn't standardize on a bad solution.
@mike I mean, yes you can combine activities and set a group as an object, but the way this is done is left as an exercise to the reader. There isn't a specification for response codes or side effects on success/failure. That's what I meant by "important details".
Yes, I can use my imagination to assemble the lego bricks the vocabulary provides into something that could maybe work, but more guidance could have been useful. :D
@volkris @Blort the problem with ActivityPub groups is that the spec has left out some very important details about how to join one, where/how to show its members, etc.