Tryit Editor v1.8

Source Code:

<!DOCTYPE html>
<html>
<body>

<h4>A list inside a list:</h4>
<ul>
  <li>Coffee</li>
  <li>Tea
    <ul>
      <li>Black tea</li>
      <li>Green tea</li>
    </ul>
  </li>
  <li>Milk</li>
</ul>

</body>
</html>

Result:

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