The furnaces are broken including blast furnaces and smokers. It takes 2 pieces of coal to smelt one item. when used lava, the lava is smelting only up to a half of an item, then the bucket gets used up as fuel. I think it is because of the most recent update.
MCPE-122116
The furnaces are broken
Resolved
Duplicate
1
This issue has already been reported. Duplicate MCPE-121863.
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