I'm not sure whether I gave this background information on the circumstances of this bug previously. Anyway, I had a particular thread which was of great interest to me, but I left it (deliberately) 'unread' for a very long time, over a year. Since I first noticed what was going on, every single day, some time in the afternoon UK time, a whole bunch of threads in the same forum as the actual unread thread, all show up as unread.
When I can be bothered, I click on the last page of each of those 'false positive' unread threads and that clears the display - until the next day. Odd behaviour by me, but I guess we all have our idiosyncrasies. Well, I finally got around to reading that genuine unread thread, and for the past two days the others have no longer appeared.
I'll add, I do have other deliberately unread threads - I intended to do some background reading/research before reading those threads. No unexpected unread threads so far - but I don't think they've passed their anniversary date yet.
When I can be bothered, I click on the last page of each of those 'false positive' unread threads and that clears the display - until the next day. Odd behaviour by me, but I guess we all have our idiosyncrasies. Well, I finally got around to reading that genuine unread thread, and for the past two days the others have no longer appeared.
I'll add, I do have other deliberately unread threads - I intended to do some background reading/research before reading those threads. No unexpected unread threads so far - but I don't think they've passed their anniversary date yet.