Example:
I put 32 Cobblestone into the Furnace and add Fuel. Now I open the recipe book and click on cobblestone (assuming I have more in my inventory). This will insert the cobblestone into the furnace slot, but abort the current smelting progress.
I believe the issue is caused by calling net.minecraft.recipebook.ServerPlaceRecipe#clearGrid before placing the items into the (1x1 furnace) grid. This momentarily invalidates the recipe, causing the progress to be reset:net.minecraft.world.level.block.entity.AbstractFurnaceBlockEntity#setItem is called because clearGrid sets the slots empty, which removes the cookingTimer.
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We're tracking this issue in MC-264236, so this ticket is being resolved and linked as a duplicate.
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