The following recipes are not working on 1.12.1b:

Pot
Banana Tree
(haven't tried other tools yet as I reverted back to 1.12c)

Hi @Honkerer, the pot and some other tool recipes are broken in the current version. They are configured to need bricks instead of iron ingots. I have a patch for these in #38 . As a workaround you can really just use bricks ;-)

Tools needing bricks is not broken. That was an intended change.

How is the banana tree recipe broken? Are you using 3 bananas and any sapling?

Banana tree is working again since using the very latest version.
Thanks for the information about bricks, I have been referring to the wiki :)

I'll continue testing and reporting issues.