It's limited to Public blogs right now (a paid feature) so we can slowly roll this out and plug holes as needed -- once I'm confident things are stable in the next few days, it'll be available to everyone for free.
You can read a bit more about the update, and I'd love to hear any feedback / ideas / bugs here! https://discuss.write.as/t/activitypub-support/64
@trwnh Hey, Update activities are now being sent out, but it sounds like Mastodon doesn't do anything with them unfortunately. Still, it should work on any other platform that accepts them.
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