Furnace Duplication Glitch

Furnace Duplication Glitch

When smelting an item, taking it out of the furnace too early can cause it to go into your inventory, and still stay in the furnace.

How to re-enact:

1) Start smelting AT LEAST 2 items, e.g. Raw Mutton.
2)When the first item is smelted, leave it. Don't remove it from the furnace.
3)When the second item is a pixel away from being smelted (the progress bar is 1 pixel away from completion), shift-click the already smelted item out.

Rather than the amount of items you removed going into your inventory, and 1 item being in the furnace, there will be the amount of items removed in your inventory and the amount you shift-clicked out + 1 still in the furnace.