You might try updating your Firefox? I'm currently on 6.0.2.

Whatever it is, it sounds like a local issue. I can assure you, as dr del said, we do have the same "go to first unread" features as any other site.

In the past, I've had similar issues pop up out of nowhere...last for a couple of days, and then resolve themselves without me doing anything except getting confused and frustrated. I never did know what caused it or what fixed it...but it was something local and had nothing to do with the site itself.

Wish I could be more help, but other than suggesting the Firefox update, and then giving it some time to see if it resolves itself, I don't know what else to do.