1.18.2 forge
2.0.8a

Not reproducible with 2.0.5

Using only sulfur to craft protein (reproducible because sulfur is part of the recipe):

Not selected recipe (not reproducible):

Using only hydrogen to craft protein (not reproducible because hydrogen is not part of the recipe):

Thanks for reporting this issue. I made some kind of mistake when changing the combiner to use Ingredients instead of ItemStacks. In my testing, I didn't encounter this issue but it should be easy to replicate. This is a very high priority issue and will be fixed soon.

Should be fixed in 2a3987c