This just started today.
Normally I read the front page, and then my "Favorites" to see what is up in my various clubs or threads I'm interested in. I then read what is green by clicking on the green number, and then I use the back button on my browser (Chrome, which is up to date).
Today, when I hit the back button, everything including the threads with no changes come up green and show 0 (zero) in the number of new posts.
If I hit the STAR for my favorites, it still comes up as expected.
So the functionality still works under some circumstances. But using the back button gives a more difficult to read screen. The first time it happened I figured I just hadn't refreshed, but then I went looking for what really happened. Of course, it is minor.
Attaching 2 images, one using the back button to get back to favorites, and the other clicking on the star to show my favorites.