Share data through CloudKit and Core Data with macOS

I'm trying to replicate the behavior of the iOS sample application provided by Apple in order to share my Core Data objects through CloudKit.

I am able to share CKRecords through Mail and Airdrop by obtaining the URL, but I cannot be able to get the iCloud Share modal window.

let sharingService = NSSharingService(named: .cloudSharing)
sharingService?.delegate = self

coredataContainer.share([ManagedObjectToShare], to: nil, completion: { [weak self] objectIDs, shareCK, container, error in

    if let error = error { 
        fatalError(error.localizedDescription)
    } else {
        self?.sharingService?.perform(withItems: [shareCK?.url])
    }
})

If I substitute the .cloudSharing for .composeEmail, the modal window opens correctly and provides me an URL to access to the object, but nothing happens when .cloudSharingis seated as SharingService.

How can I accomplish this?