Subcollections are not filterable

APIs
1

Hello!

In the example query below, MainCollection and secondaryCollection have multi-references, respectively. And I’m unable to search by a value in a multi-reference field when querying the main entries. Would able to make sub-collections filterable?

query MyQuery {
  mainCollection(limit: 2) {
    items {
      secondaryCollection(limit: 10) {
        items {
          tertiaryCollection(limit: 10) {
            items {
             ...
            }
          }
        }
      }
    }
  }
}