Put the summary of the bug you're having here
During the new snapshot when you place coal in a furnace it crashes
What I expected to happen was it to act normal and smelt
Describe what you thought should happen here
I thought it would smelt normally
What actually happened was it crashed
Describe what happened here

Steps to Reproduce:
1. first get a furnace
2. then get coal
3. lastly put the coal in the furnace