Conversation

@jupiter_rowland @strypey @mikedev @LaurensHof

And FEP-c390 is a predecessor of FEP-ef61. It describes a method of linking ActivityPub actors to cryptographic identities (using signed attachments). That enabled permission-less migration of followers, but not posts. Later, a method of linking *any* ActivitiyPub object to cryptographic identity was discovered, and that eventually became FEP-ef61

I don't think FEP-c390 should be used for migrations or nomadic identity, but it might still be useful as a cryptographic equivalent of rel=me linking.