There’s apparently no tag for this 
I think it’d be a good idea to add it. Even if it’s just “a modal”, it has a very distinct purpose, content and features and I wish I were able to search efficiently for topics about post revisions / history, by using a tag.
What about something like #edits? IMO that is fairly broad to cover revisions, edit diffing and edit reasons.
I’m not sure what trust level is able to create tags (imo it should be 3) but I’ve tagged this post revisions 
Thank you! Can it be added to Post history buttons labels are all truncated because of a lack of space
edit: of course, I could have added it myself… Do I start forgetting how Discourse works? 