title: What are usage examples for NSFileProviderExtension in Swift?
body: <p>It seems like the <code>NSFileProviderExtension</code> inherits from <code>NSObject</code>.
  The apple documentation <a href="https://developer.apple.com/documentation/fileprovider/nsfileproviderextension" rel="nofollow noreferrer">here</a> does not have any usage examples.</p>
  
  <p>Thanks in advance.</p>