Thanks for your post - especially, telling your experience with a similar thing. That is interesting - since every page should automatically refresh when you initially open it.
However, I did plenty of refreshes and created enough new windows in about a 3-4 hour period - every time - the little red rectangle with a '1' in it showed up.
Not to mention, the 'account' alert (the bell) was changing like normal with new posts to threads I have subscribed to - only that one alert seemed to be "stuck" on as 1 new alert/image/media reported.
I am already well-acquainted with the 'Mark media viewed' button on the Life-bits/Media page. Tried it. Nope - no change.
I even clicked on several of the most recent additions to the list to "register" them as having been seen. Nope - no change - the little red rectangle with a '1' in it refused to go away.
BTW - I don't remember ever having seen this happen before.
I am somewhat of a "power user" by way of using tabs and windows - so that I can leave certain pages where they are while I "run a rabbit" or some such thing away from that point - and, ultimately, just close the extra window - and, be left where I started on the original page.
Generally, I leave the CC main page as is after I log in and put alerts and other lists in tabs. I open a forum from the main page into a new window. I open a post from a list into a new window. I do searches in a new window and open selected posts from that list into tabs on that same window.
"I have a system that serves me well."
I can easily end up with several tabs and windows open at the same time while I am working on a reply to a post, for example. Of course - most of the time - in such a case - they all end up being closed before I move on to the next thing...
Anyway, for me, opening and closing windows "as I go" is a regular thing.
This is/was definitely a 'glitch' of some sort, in my opinion.
I guess "we shall see" what happens after the next entry is added to the Life-bits list...