Placing a hopper next to a furnace, if the hopper is supplying something to the furnace, and the furnace runs out of coal, the hopper puts it in the fuel section of the furnace.
Placing a hopper next to a furnace, if the hopper is supplying something to the furnace, and the furnace runs out of coal, the hopper puts it in the fuel section of the furnace.
Duplicate of MC-5748.