In our docs we had a structure:

1.A. Sub-category

1.A.x Sub-sub-category

And while I opened our knowledge base page for the Category I didn't see the Sub-category there. It only then appeared when I copied an article in it.

I guess before that it was seen as empty, although it had four Sub-sub-categories in it.

Would like to see the Categories and Sub-categories then too when there are no articles directly under them.