This worked for me. Now the webView(_ webView: WKWebView, createWebViewWith configuration: WKWebViewConfiguration, for navigationAction: WKNavigationAction, windowFeatures: WKWindowFeatures) -> WKWebView? gets called then the webpage calls window.open in javascript. I can now choose to ignore it, open it in the same view, launch the UIApplication.shared.open .. to switch to safari, or even implement popup or tabbed view too. Thanks