chromium/third_party/blink/web_tests/editing/inserting/6104369.html

<style>
blockquote {
    color: blue;
    border-left: 1px solid blue;
    padding-left: 2px;
    margin: 0px;
}
</style>
<body>
<div>This tests for a bug where hitting return at the end of a paragraph inside a blockquote would create an extraneous empty quoted paragraph.  You should see "line one" (quoted), "" (unquoted), and "line two" (quoted) below.</div>
<div id="div" contentEditable="true"><blockquote type="cite"><div id="test">line one<br>line two</div></blockquote></div>
<script>
if (window.testRunner)
    testRunner.dumpAsText();
test = document.getElementById("test");
window.getSelection().collapse(test, 1);
document.execCommand("InsertNewlineInQuotedContent");
if (window.testRunner) {
    div = document.getElementById("div");
    div.innerText = div.innerHTML;
}
</script>
</body>