phiofx@laxla this shouldn't happen if you implement on the server side according to the pattern described here https://www.w3.org/TR/activitypub/#source-property (so servers that respect the protocol will play along, propagate the "source" bit of the Activity along with the rest etc.). What seems non-trivial is to get your desired list of clients properly use that extra material or at least have a workable fallback. So it would not be "defederation" but it might amount to the same from a user perspective if they don't see it.
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