Patchouli documentation on subcategories

Nightbulb_

I am making a book that requires subcategories. I've looked online, and I've seen that people have used subcategories, however, it is never mentioned in the mod documentation.
this is the documentation I'm looking at: https://vazkiimods.github.io/Patchouli/

can someone direct me to where this is documented, if it is?

williewillus

A subcategory is simply a category that has its parent property set. They behave in pretty much the same way as root categories.