lang-pseudo-class-disconnected.html

<!DOCTYPE html>
<html>
<link rel="help" href="https://drafts.csswg.org/selectors/#lang-pseudo"/>
<body>
<div id="container" lang="zh"><span></span></div>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script>
test(() => {
    let target = container.querySelector('span');
    assert_true(target.matches(":lang(zh)"));
    target.parentNode.remove();
    assert_true(target.matches(":lang(zh)"));

    const anotherContainer = document.createElement('div');
    anotherContainer.innerHTML = '<div lang="fr"><span></span></div>';
    target = anotherContainer.querySelector('span');
    assert_true(target.matches(":lang(fr)"));
    document.body.append(target.parentNode);
    assert_true(target.matches(":lang(fr)"));
}, ":lang pseudo class should work in a disconnected subtree");
</script>
</body>
</html>

chromium/third_party/blink/web_tests/external/wpt/css/selectors/i18n/lang-pseudo-class-disconnected.html