<!doctype html>
<script>
var result = "FAIL";
if (opener != null) {
  result = "FAIL (did you open this page in a new tab?)";
} else {
  var w = window.open("", "test_name");
  if (w.location.href !== "about:blank") {
    result = "FAIL (didn't open an about:blank browsing context)";
  } else {
    w.close();
    result = "PASS";
  }
  document.write(result);
}
</script>