Does anybody really implement pure #ActivityPub (and ActivityStreams 2)? Looking at the actor (and/or attributedTo) fields, for example. There can be multiple of each. The JSON representing them could have a string/URI, a mapping, a Link, or a list of a combination of those types. Assuming a server handles all those variations (I doubt any server does), how does it interpret it in a context where a specific inbox/outbox POST is authenticated using HTTP signatures (single actor)?
