As a user who watches a given discussion, I want to be able to mass revert any flow actions (edits to existing comments, hiding of content, adding new comments), so that vandalism can be fixed quickly once it is noticed.

E.g.: I was not able to find a way to "mass unhide" several comments hidden by an anonymous user on Portuguese Wikipedia. On normal talk pages, I could just click "undo" (or "rollback" when I have the appropriate user right) and they would all be restored (and the edits marked as bot edits, in the case of rollback).