<!DOCTYPE>
<html>
  <head>
    <meta charset="utf-8">
    <script>
      "use strict";
      var response = {
        tabs: false,
        cookie: document.cookie,
      };
      try {
        browser.tabs.create({url: "file_sample.html"});
        response.tabs = true;
      } catch (e) {
        // ok
      }
      window.parent.postMessage(response, "*");
    </script>
  </head>
</html>
