Infinite XP on touch devices

Steps to reproduce (I haven't tested this on Windows 10 or Xbox One)

1 - Cook something using a furnace (e.g. iron ore), I recommend using 64, it will be more easy to see.

2 - Have the same item in your inventory (e.g. iron ingot), in a way that is impossible to have more items in the same slot.

3 - When it finishes, tap on the cooked item and try to move it to the slot with the same items.

It will not move the item because it hasn't any free space, but it will give you the XP.