chromium/third_party/blink/web_tests/editing/pasteboard/undoable-fragment-removes.html

<!doctype html>
<script src="../../resources/testharness.js"></script>
<script src="../../resources/testharnessreport.js"></script>
<script src="../assert_selection.js"></script>
<script>
test(() => {
    assert_not_equals(window.internals, undefined,
        'This test requires window.internals to access clipboard');

    assert_selection(
        [
            '<div contenteditable>',
                '<div>^foo</div>',
                '<div>bar|</div>',
            '</div>',
            '<div contenteditable id="paste"><br></div>',
        ].join(''),
        selection => {
            selection.document.execCommand('copy');
            selection.collapse(selection.document.getElementById('paste'), 0);
            selection.document.execCommand('paste');
            selection.document.execCommand('undo');
        },
        [
            '<div contenteditable>',
                '<div>foo</div>',
                '<div>bar</div>',
            '</div>',
            '<div contenteditable id="paste">|<br></div>',
        ].join(''));
});
</script>