The bubble is not working for me as you describe. I logged off, logged back on later. An old thread had been updated, and moved to the top of the list. The bubble was gray.
Right now, one cannot distinguish between:
1. a thread previously viewed having new replies,
2. a thread previously viewed having no new replies.
Post Edited (BOB 46) : 10/13/2018 7:52:39 PM (GMT-6)