s(sheet.cssRules[0].cssText, redStyleTexts[1]);

  const sheet2 = new CSSStyleSheet({});
  assert_equals(sheet2.title, null, "The title attribute must return the title or null if title is the empty string");
  assert_equals(sheet2.ownerNode, null);
  assert_equals(sheet2.ownerRule, null);
  assert_equals(sheet2.media.length, 0);
  assert_false(sheet2.disabled);
  assert_equals(sheet2.cssRules.length, 0);

  sheet2.insertRule(redStyleTexts[1]);
  assert_equals(sheet2.cssRules.length, 1);
  assert_equals(shee