How to display a catalog without products (modx and minishop2)?

Question

MODX

For example, there is such a structure of the Catalog: Catalog of
Goods:
Subcategory1
Subcategory1
Subcategory2
Subcategory3
Subcategory2
Subcategory1
Subcategory2
Subcategory3
Subcategory1
Subcategory1
Subcategory2
Subcategory3
How can I build only a menu according to the Catalog using Wayfinder, I ignore all documents, but! also ignoring subcategories and products, i.e. build a menu using only Subcategories?
Those. if there is at least one product in the Product Catalog - ignore it?
I do things like:

Need purely lists of categories (in the example Subcategory), what to do?

Answer 1

The question, most likely, is not relevant for the author .. But maybe it will help someone else ...
try &where=`{"isfolder":1}
as a result, the construction will look like this: