I use this function all the time to mark sub-forums as read, but it has suddenly changed. Now it doesn't just make the icon inactive like before, it first takes me to a loading screen, and then it takes me to the forum index for that particular sub-forum, which is useless, when I was on the main forum index page.
Niall, what have you done?
Or is this just happening to me, I notice the Editor Buttons don't work either.