title: PWA Offline auth
body: <p>What is the best way to keep a user authenticated in a PWA when an app is revisited when offline.</p>
  
  <p>Example..</p>
  
  <ol>
  <li>User visits web app with an internet connection.</li>
  <li>User Logs in and downloads all the needed data (indexeddb).</li>
  <li>The user closes the page.</li>
  <li>User comes back to the page (No internet).</li>
  <li>User is already logged in..</li>
  </ol>
  
  <p>5 is the part I need advise on, the log needs to be secure so tokens in cookies/localstorage won't be good enough. </p>
  
  <p>Any advice please?</p>