2025-07-29 UTC
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[manton] > ActivityPub defines the `Block` activity for client-to-server (C2S) use-cases, but not for server-to-server (S2S) – it recommends that servers SHOULD NOT deliver Block activities to their `object`. However, Mastodon will send this activity when a local user blocks a remote user. When Mastodon receives a `Block` activity where the `object` is an actor on the local domain, it will interpret this as a signal to hide the actor’s profile an