Codebase Browser
chromium
Go to App

chromium/third_party/blink/web_tests/fast/forms/select-popup/popup-menu-appearance-long.html 

<!DOCTYPE html>
<meta name=fuzzy content="maxDifference=0-3; totalPixels=0-100">
<script src="../../../resources/testdriver.js"></script>
<script src="../../../resources/testdriver-vendor.js"></script>
<script src="../resources/picker-common.js"></script>

<select style="width: 10px">
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
  <option>very very very long option</option>
</select>

<script>
  window.onload = openPickerAppearanceOnly(document.querySelector('select'));
</script>