Hi, i miss the feature where it was possible to use the trowel to place randomly stairs and slabs upside down :( my Version: 1.21.1-0.13.4 (NeoForge)

I remember in 1.20.1-0.9.1 it was possible?

Trowel was added in 1.21.1-0.13.1 so it must have been another mods trowel. Can you describe how it worked in detail then I can maybe mimic that behavior for mine.

Ah, yes you are right, your mod was in ATM9, but the Trowel did not exist, it was from Quark.

I did some Example Videos how it is and what I was expecting :)

Your Mod:
https://imgur.com/a/bUEtrXP (Stairs)
https://imgur.com/a/P2ZJFcE (Slabs)

Quark:
https://imgur.com/a/KmN0W1y (Stairs)
https://imgur.com/a/dcEV1vL (Slabs)