This is new- just over the past few hours. Every post I comment in is now marked "unread" until someone else posts. This doesn't happen to posts where someone else's comment is the last one - as soon as I read it, it goes to "read" status. But if the last comment is my own, it stays at "unread" status.
43 times. Even refreshed the page. Deleted the post and it goes to read. Repost, and back to unread. On any post in any thread where I am the last poster. REally bizarre.