title: Using JavaScript to replace ">" text
body: <p>I'd like to do a <em>Greentext</em> plugin for Firefox using Greasemonkey,but without jQuery.</p>
  
  <p>Here's what I did:</p>
  
  <pre><code>&lt;head&gt;
  &lt;script type="text/javascript"&gt;
      function highlight() {
          var elm = document.getElementsByClassName("mainWrapper");
  
          for(i = 0; i &lt; elm.length; i++)
          {
              elm[i].innerHTML.replace("&gt;","pony");
          }
      }
  
      alert("PONY");
  &lt;/script&gt;
  &lt;/head&gt;
  
  &lt;body onload="highlight()"&gt;
  &lt;div class="mainWrapper"&gt;&lt;span class="noob"&gt; &gt; N00b &lt;/span&gt;
  &lt;/div&gt;
  &lt;/body&gt;
  </code></pre>
  
  <p>This is a testing version for the function, I did it because I think that the problem was Greasemonkey, but it doesn't work yet.</p>
  
  <p>Can you help me? I'm not very good at programming and I don't know how to script on JS very well.</p>