"Mark all read" should not mark new notifications not yet displayed.

So I was on the notifications page and, after reading the notifications and doing stuff based on them (and taking a phone call, etc.) I went back to click "Mark all read".

As my finger hit the button, I saw the "New Notifications" alert. Unfortunately, it was too late and I clicked and not only did the notifications I'd seen go away, so too did the new, unseen ones.

Perhaps the "Mark all read" button could be changed to apply only to those already displayed? Or at least not work if the "New notifications" message is displayed?