chromium/third_party/blink/web_tests/editing/selection/modify_extend/extend-by-word-001.html

<!DOCTYPE html>
<script src="../../../resources/testharness.js"></script>
<script src="../../../resources/testharnessreport.js"></script>
<script src="../../assert_selection.js"></script>
<script>
selection_test(
  [
    '<div contenteditable>',
      '<div>foo<span style="white-space:pre">\t|</span>bar</div>',
    '</div>',
  ],
  selection => selection.modify('extend', 'forward', 'word'),
  [
    '<div contenteditable>',
      '<div>foo<span style="white-space:pre">\t</span>^bar|</div>',
    '</div>',
  ],
  'Extend word from after TAB character');
</script>