@cheeaun Yeah, they can break too if someone else takes your old username. And, yeah, old permalinks redirect to new permalinks with 301 Moved Permanently!

At-mentions will be rendered as was, although links will work.

@hongminhee ah ok, I was kinda thinking that `oldusername/post/ID` will just redirect to `newusername/post/ID` even when `oldusername` is taken — only `post/ID` matters and permalink stays permanent.

As for the at-mention change render, I remember Twitter does this 🫣 (with entities object in the API) — so it's less confusing when reading posts with changed usernames.