Добавление WebView к NSPopover не показывает WebView, только NSView

В AppDelegate Init() У меня естьДобавление WebView к NSPopover не показывает WebView, только NSView

popover = NSPopover() 
popover.behavior = .Transient 
popover.contentViewController = ContentViewController()

Теперь в ContentViewController: NSViewController

override func loadView() { 

     view = NSView() 
     view.translatesAutoresizingMaskIntoConstraints = false 
     view.addConstraint(NSLayoutConstraint(
      item: view, attribute: .Width, relatedBy: .Equal, 
      toItem: nil, attribute: .NotAnAttribute, multiplier: 1.0, constant: 580)) 
     view.addConstraint(NSLayoutConstraint(
      item: view, attribute: .Height, relatedBy: .Equal, 
      toItem: nil, attribute: .NotAnAttribute, multiplier: 1.0, constant: 425)) 

     NSUserDefaults.standardUserDefaults().registerDefaults(["UserAgent": "Tick Mac App"]) 
     let url = NSURL(string: tickExtensionURL)! 
     var request = NSURLRequest(URL: url) 

     var webView = WebView(frame: view.bounds) 
     webView.mainFrame.loadRequest(request) 
     view.addSubview(webView) 

    }

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