Tree view fields can be enabled for an instance in the License tab in the cloud manager. Please contact support to do this for you.
It's a view only field.
The administrator who creates the field defines the filter.
You cannot edit the field in single or batch edit mode.
The field can be added to Layer, List and Virtual Schemas.
The field must reference a single or multitagbox field.
You cannot select tree view fields in advanced filter editors or add them as sorting fields. Tree view fields will not show up in the List Item Browser.
To see tree view fields in the UI you must add them to a Channel or List Filter.