It would be nice to be able to "go back in time" when it comes to "unread posts". I have not studied in detail how MM keeps track of this, but I'm guessing a "last seen postId" or a "last seen postDate" or something similar. Anything greater than this is "unread". Anyway, what I would like to see is a way to "undo" or "go back in time" on nn unread states.

Say I login today, I have 33 unread/new messages. But I want to go back to the "unread count" I had the last time I logged in before today. So I select "Yesterday" (from my list of "time machine" markers, based on login time for example) and MM refreshes showing me how it would look if MM thought I logged in yesterday.

What I'm after, I guess, is a way to find "recent" but no longer "new" posts.