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Issue description:

Steps to reproduce:

Currently only seen in my Capitalia modpack, but you can't smelt any of the dusts from Mekanism or any other mod.

1. Place dust into smelter's input slot
2. Provide power
3. See how it won't smelt

Version (make sure you are on the latest version before reporting):

Forge: 14.23.5.2854
Mekanism: 9.8.3.390
Other relevant version: Mekanism Generators & Tools 9.8.3.390

In general, 1.12 isn't supported by us any longer.

You'll need to remove mods to work out what's interfering (I recommend removing half, checking, then halving again if it still occurs).

And if you're using Crafttweaker, check without your scripts.