title: Printing from a progressive web app
body: <p>I have a web app that uses the following javscript code:</p>
  
  <pre><code> prnWnd = window.open();
   prnWnd.document.title = "Printing...";
   $('&lt;p style="font-size: 20px"&gt;Please wait while the content is rendered...&lt;/p&gt;').appendTo(prnWnd.document.body);
  </code></pre>
  
  <p>Normally, this opens a new browser window with a text inside. Works perfect on a browser, but when I add the manifest and service worker related code to launch the page as a progressive web app, this no longer work. It simply opens a new window, empty. Any ideas?</p>