title: how to remove earliest lines from javascript div
body: <p>I'm adding lines to a <code>div</code> element with javascript using append:</p>
  
  <pre><code>myDiv.append("sometext &lt;br&gt;");
  </code></pre>
  
  <p>After say 20 lines, I'd like to remove the earliest line, and keep removing lines as I add new one to prevent it from getting to large. What is an easy way to do this?</p>
  
  <p>Thanks.</p>