chromium/third_party/blink/web_tests/editing/inserting/5378847.html

<p>This tests character insertion on a line with an unrendered text node.  You should see 'Hello' and then 'World' below.</p>
<div id="div" contenteditable="true"><table border="1"><tr><td>Hello</td></tr></table><br></div>

<script>
if (window.testRunner)
    testRunner.dumpAsText();
    
var div = document.getElementById("div");
children = div.childNodes;
br = children[1];
text = document.createTextNode('\n');
div.insertBefore(text, br);
sel = window.getSelection();
sel.collapse(div, 1);
document.execCommand("InsertText", false, "World");
</script>