<!DOCTYPE html>

<html>
<body>
<script type="text/javascript">
/* exported openWindow, navigate, check */
var nav, win;

function openWindow() {
  return new Promise(resolve => {
    win = window.open(window.location);

    win.addEventListener("load", function listener() {
      nav = win.navigator;
      resolve();
    });
  });
}

function navigate() {
  win.location = "http://example.com/";
}

function check() {
  return "mozAddonManager" in nav;
}
</script>
</body>
</html>
