title: Can two WKWebViews be linked via the opener property?
body: <p>I'm opening a WKWebView from another, and would like the two to be able to communicate with each other via JavaScript.</p>
  
  <p>The following code opens two Web views - I can inspect them with the Safari debugger. But the <code>opener</code> property of the second Web view is <code>null</code>.</p>
  
  <pre><code>class MyVC: UIViewController {
      override func viewDidLoad() {
          ...
          // "webView" is the first web view. Open a second one...
          webView = WKWebView()
          webView.uiDelegate = self
          webView.evaluateJavaScript("window.open('about:blank');")
      }
  }
  
  
  extension MyVC : WKUIDelegate {
      func webView(... createWebViewWith ...) -&gt; WKWebView? {
          let newWebView = WKWebView(frame: webView.bounds,
                                     configuration: configuration)
          newWebView.load(navigationAction.request)
  
          let vc = UIViewController()
          vc.view.addSubview(newWebView)
          navigationController?.pushViewController(vc, animated: true)
  
          return nil
      }
  
  }
  </code></pre>
  
  <p>Is there a way to set the opener property?</p>