Burner inserter fuels itself from the spoilage in the biochamber.
Actual outcome
Burner inserter ignores the spoilage and runs out of fuel.
Note
If you set the filter on the burner inserter to exclude carbon fiber, it will fuel itself. Nothing is preventing the inserter from taking the spoilage.
Note for whoever works on this: this is due to inserters iterating output inventories fully before moving on to the next. It results in the inserter grabbing a non-fuel item from inventory 1, then bails on grabbing fuel from inventory 2 because it already has a non fuel item from inventory 1.
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