Bug/Issue: Removing card prices

Hey, this is something small that I ran into a while back that took me a while to figure out. It should probably be fixed.

Basically, when I want to take one of your cards for sale and remove its price, I just click on its price and enter "0" and hit Enter. This sets the price to N/A on the page and it won't be for sale. Great.

But I noticed that if you click on its price and then leave the value blank and then click elsewhere, this will also set the price to N/A on the page.... but it doesn't update whatever database so that when you refresh the page it'll have the old prices.

I only noticed this because I set some prices to N/A in this latter manner and then a user made an order proposal involving them and I was like "wtf." Basically, it's very confusing that the former method of updating prices works and the latter doesn't, when both of them end up showing the price as N/A while you're doing the updating.

The obvious solution is to either make it so that leaving a price value blank actually sets it to N/A and removes it from the market, or that the page just goes back to showing the old value.