Faceted Search does not show custom features filters

[Salvatore Ucchino]

Prestashop version: 1.7.5.2

Faceted search version: 3.5.0

Custom features filters not showing on the product/category page. I solved this problem in the past but I don't remember the way anymore, I remember that there was a bug in the query that extracts the filters but not the custom ones. Can anyone help me out? Thanks.

[Demacri]

Check if in that category exist products with different values for that specific feature. If there's only one, it will not be displayed.
Example:
Cat 1
    Product 1 Composition X
    Product 2 Composition X

Composition filter will not be displayed. 

Cat 1
    Product 1 Composition X
    Product 2 Composition Y

Composition filter will be displayed