Until yesterday, if I had read a Topic, it’s title in the list of topics would turn grey. Now they are all staying black, so I can’t tell which I have read, and which I have not. This makes it very difficult to track updated Topics and to determine which Topics require attention.
I have tried a hard-refresh (Ctrl-F5) and have also cleared my Cookies for this domain. Neither has helped.
P.S. I use Firefox exclusively, and run Win8.1 on my laptop.