I would guess the item was “ cabin crew”. Only the fairly new Bus are equipped. We don’t have a written procedure about it. Normally the CFA would have to press a button in the Flight Attendant Panel when they are ready and it will remove the blue item. But sometimes they forgot or during a long taxi the item will come blue again if the button has been pushed more than 7 min ( not sure exactly how many minutes). In any case, you can disregard it assuming you have checked the cabin report before take off or landing. No caution/warning will be triggered in any case.