Infinite experience with items from furnace

To recreate this bug you will need a minimum of 65 smelted items, seems to work with anything that goes into the furnace, I was able to gain over 140 levels in roughly an hour with iron/gold.

The bug happens when you try to add a stack of smelted items in the furnace to an existing stack of items in your inventory.  If the result is over 64 the items will return to the furnace and you can repeat and gain experience on each subsequent try. 

For example if you have 44 Cracked Stone Bricks in one of your inventory slots and there are 21 Cracked Stone Bricks in the furnace and try and merge the two stacks, it will give experience, check if the item stack can be merged, then instead of just adding 20 and tossing the 1 somewhere else, it adds the entire stack of 21 back into the furnace so you can try the process again.

I think this bug is newly introduced, but a friend was able to confirm that it worked on an old Playstation version so possibly not.