chromium/third_party/blink/web_tests/editing/style/apply-style-atomic.html

<!DOCTYPE html>
<html>
<head>
<script src="../../resources/dump-as-markup.js"></script>
</head>
<body>
<div id="edit" contentEditable="true">1<progress><a style>2</a></progress></div>
<script>
Markup.description('Test that WebKit does not crash when we apply style to atomic elements ' +
'and that the style is not applied inside atomic elements.')

function select(node) {
    var range = document.createRange();
    range.selectNodeContents(node);
    window.getSelection().addRange(range);
}

var edit = document.getElementById("edit");
select(edit);
document.execCommand("createlink", false, "a");
Markup.dump(edit);
</script>
</body>
</html>