Create a new trade.
Do not click anything else except:
scroll down and select the tf2 currency category, click two weapon icons.
scroll up and click on the ? in the second wishlist, it should be added to the first wishlists set thus breaking the wishlist.
Sorry I don't quite understand.
Open up your shop and show all items. Select a five items, for example it could be any number, and then exchange them out. Wait for the shop inventory to refresh after exchanging the items.
Bug: The page should say five items selected but when you press the "deselect" items to reset the selections it cannot because the items are gone.
Yes it's a minor bug there (the inventory counter won't update as well if you have noticed). You are supposed to reload the page for a full refresh. This scripted auto-refresh is not supposed to be perfect.