not sure if its bagnon or not causing the issue, but when opening the northrend supply gift boxs you get from the quests, sometimes the box doesn't go away. It stays greyed out. You cannot click on or move the greyed out box. Opening/closing your inventory does not clear it. If you try and clean up your bags, it gets stuck in a nonstop loop trying to move items and you have to /reload. Doesn't happen every time. Possibly relating to the time it takes to roll the items from the loot table and put them in your inventory when it takes several seconds.