"Class" value="UpgradeRated"

[Fair Player [PL]]

As in tittle how to get this working?
It is kind of property in blocks.xml of older alphas. Wet concrete "pourcedConcrete" block was using this to upgrade self to dry concrete. They removed even this .
Copping this instruction to A20 xml causes that the block disappear. 
Can not find in files what the "name="Class" is calling.

Edited December 10, 2021 by Fair Player [PL] (see edit history)

[JaxTeller718]

Hopefully they did not remove this, it will break many mods.