That would implicitly make each actor it's own namespace (in the sense that DNS is a namespace), and allow easy(-ier) movement of actors between federated instances, by greatly decreasing potential URL breakage.
It could also lead to increased compatibility with future p2p uses of ActivityPub.
That would make URLs non-permanent, isn't that a bad thing?
@doenietzomoeilijk instances are run on volunteer basis, so they're already non-permanent in the sense that any instance in the network can die at any point.
Building a network that requires everything to stay online perpetually makes the network fragile IMO, so I think we should rather design so that we allow some degree of non-permanence.
@doenietzomoeilijk if the posts are stored in a format where the instance uses internal ids pointing to actors (which can be taken care of almost for free when receiving the post), then you wouldn't have to change anything in the posts when the actor changes location. The internal actor-id should ideally be unrelated to any other specific attribute of the actor.
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