Handling forum posts in aggregate

Sorry, I could not figure out a suitable category to post this.

With the new forums active again, many topics that were marked "read" became live again. I've numerous entries that I had previously processed, but now I have to go to each one open and close it to remove it from the unread list.

Is there a way to mark multiple or all entries of a category and mark it "read" ?

Yes, down in the bottom right corner is a "dismiss" button.