I just noticed that, if I look up a #Lemmy or #Piefed community on #Mastodon, I'll get a profile page but no posts!

Is that a bug in Mastodon? Or is there no standard #ActivityPub protocol for fetching content from a person/group that you aren't already following?

I seem to recall Mastodon adding a “fetch content from the other server” feature recently, but it sounded like a Mastodon-specific protocol extension was involved. That's…not great. It really should be universal.