Ancient debris appears to stop cooking when under 8 items in the stack, in furnaces or blast furnaces.
Steps to reproduce:
Create a new world, obtain 4 ancient debris, 1 coal, 1 furnace. Place furnace block and place remaining items in furnace inventory, observe the lack of progress on cooking debris into scrap.
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We're tracking this issue in MC-249409, so this ticket is being resolved and linked as a duplicate.
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