Previews merging source contacts into a target contact.
This endpoint performs a dry run without deleting or updating any contacts. A preview of the updated target contact is returned, but no data is changed in the Contact List.
To perform the actual merge, use Merge Contacts.
Members are typically associated with a contact, each having a distinct member and contact ID. When passing the ID as a parameter, avoid presuming the IDs are identical since they represent separate entities.
You can only call this method when authenticated as a Wix app or Wix user identity.