@evanEvan Prodromou 
@kopperkopper 
mentioned the async problem; if there’s no external contexts to fetch, then the recieving server can explicitly reject the request if it is incorrect.
@gugurumbeVivien (toujours dans le déni) @kopperkopper I don't think that's the model of ActivityPub. It's made to allow reading remote objects.
Most implementations pre-load or compile in the external contexts. I agree, it's a big performance hit to load context URLs at runtime.
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