(Fact with story) I chucked some metal ore and coal into my furnace and quickly went to bed. When I got up i hastily ran over to the furnace to see if it had finished it's work, but no it had not. I was a bit disappointed when I discovered this and felt that this should be an possible update.
(Pure fact) When using the bed, the furnace(s) will pause its progress till the sleeping is over. I feel that this should be updated.
When you use a bed, the game does not simulate the time you spend asleep. This means monsters will not spawn, furnaces will not cook, and trees will not grow. I think that this is a bug, but it could be a deliberate penalty for using a bed to skip nighttime.
(Pure fact) When using the bed, the furnace(s) will pause its progress till the sleeping is over. I feel that this should be updated.
PLEASE ALSO SUPPORT:
Sabata & Grey Acumen's "New Nether"
Grey Acumen's Minecraft 2.0 Suggestion Series
The caveman's secret weapon
I support Carrier Eagle
I support Power gloves
I support Coal Powered carts delay