Hrefna (DHC)Yep, that project fits in a different niche than what I'm looking at: it's a different syntax entirely. A replacement for JSON-LD rather than something that interoperates with it as it is used in practice.
Another example is the largely defunct #LitePub: https://litepub.social It was an attempt to clean up and simplify some the semantics around #ActivityPub and provide a little more of a server specification along with it, but it doesn't use AS2 vocab.
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