_equals(image2.fetchPriority, "low", "low fetchPriority is a valid IDL value on the image element");
    assert_equals(image3.fetchPriority, "auto", "auto fetchPriority is a valid IDL value on the image element");
    assert_equals(image4.fetchPriority, "auto", "invalid fetchPriority reflects as 'auto' IDL attribute on the image element");
    assert_equals(image5.fetchPriority, "auto", "missing fetchPriority reflects as 'auto' IDL attribute on the image element");
  }, "fetchpriority attribute on <image> e