There is an intermittent glitch when adding cards to tradelist where the quantity reverts back to the original number, and then the system adds a line item to the card with 0 in inventory and 0 in tradelist. When you click the quantity that opens up the small window to manual adjust quantities, you can see the 0/0 line item, and then when you change the correct line item to what you want it show, and then save, the 0/0 line item disappears. This problem is intermittent with no discernable pattern. It happens pretty randomly, but once it starts, it usual does not resolve for a while, even after closing the browser and trying again. Is this a known bug?

EDIT: This appears to only happen when adding 1 card to tradelist when there is 1 card in inventory. When adding 1 card to tradelist when there are 2 or more cards in inventory, the problem does not appear to happen, and it resolves the bug for several adjustments, but eventually the bug happens again when adding 1 to tradelist with 1 in inventory.

2nd EDIT: I can confirm that the bug only occurs when the card is marked as English.