The furnace GUI is not working as expected.
You cannot highlight the bottom slot (fuel),
and although you can put smeltable items in the top slot, it is impossible to retrieve them without breaking the furnace block itself.
Steps to Reproduce:
1. Place furnace block.
2. Place items into top slot.
3. Notice how the items in the top slot cannot be retrieved again.
Duplicate of MCPE-2453, please use the search function to see if your bug has already been submitted. Currently over 59% of tickets are being closed as duplicate.