To get a sense of how that would work, check out #InteroperableFacebook, a video and essay I put together with @eff to act as a kind of #DesignFiction, in the form of a user manual for a federated, interoperable Facebook:
https://www.eff.org/interoperablefacebook
He points out that this kind of mandatory interop is a preferable alternative to the unconstitutional (and unworkable!) speech bans proposed by #Florida and #texas
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