Put the summary of the bug you're having here
When you put a item in the top part then go to enter the fuel it won't let you put in the fuel and you can't get your items back unless you destroy it

What I expected to happen...
is for me to put in the fuel

What actually happened was...:
It doesn't allow you to put in the fuel

Steps to Reproduce:
1. Craft a furnace in survival mode and place it anywhere
2. Then click and put item in top box
3. Then click on the bottom to put in fuel