How do you clear all the numbers after tracking a category?

I stupidly selected “tracking” on an entire forum, and even after switching back to “normal,” I still see tons of blue and grey number bubbles on all the threads in that category. Is there some way to clear these unwanted notification or do a “mark all as read” for the entire category, etc.?

Every thread in that category now says that I’m tracking it. I would have to enter every thread and set each one to “normal.” Is there a way to set all that category’s threads to normal in one operation?