@evan IDK for sure - but Mastodon invites subject changes because of how replies get presented, because it does not use threaded display, which is also a feature that birdsite „tacked on“ rather shoddily, which is why threads on birdsite aren‘t always „threaded“ right away. I guess it must have been a background task.
Socially, I have dialectic opinions on this one. „It‘s okay sometimes“. Not „rarely“ when doing politics or debate - for example.