As noted elsewhere I migrated my personal Mastodon account to a new instance.
Under Customize > Post Signature, in the settings of my federated blog @paolo@journal.paoloamoroso.com I added the Mastodon handle of my personal account. This way replying to my blog’s toots from the Fediverse also mentions my Mastodon handle from which I can reply and interact.
This worked fine with the old Mastodon instance @amoroso@fosstodon.org but not the new one @amoroso@oldbytes.space.
Just so I’m sure, is the issue just that the old posts aren’t mentioning your new handle inside Mastodon / the fediverse?
If so, I believe this is because we don’t send out updates to the fediverse when a signature changes (this would be a ton of requests all at once). But if you want to force the update, you could try editing a post, changing a single character (like adding a space), and then pressing “Update”. This will send out an updated post to the fediverse. But just a heads up I’m not sure if it will actually mention your new account in Mastodon – it’s handled entirely on their end, and I haven’t personally tried it out.
I’ve just published a new post. I don’t mind old post not having the new Mastodon handle but I migrated over a month ago and the new handle in the blog signature is still missing from federated toots.
Never mind, the toot now does include the new handle. I didn’t notice at first as my new instance runs a Mastodon fork that presents things a bit differently in the toot editor. But I tried an instance that runs mainline Mastodon and the handle shows up.