
  assert_false(element instanceof HTMLElement, "Should not be an HTMLElement");
  assert_false(element instanceof HTMLSpanElement, "Should not be an HTMLSpanElement");
}, "Upper-case non-HTML element without a prefix");

test(function() {
  var element = document.createElementNS("test", "html:SPAN");
  assert_equals(element.namespaceURI, "test");
  assert_equals(element.prefix, "html");
  assert_equals(element.localName, "SPAN");
  assert_equals(element.tagName, "html:SPAN");
  assert_true(element instance