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  <head>  </head>
    <div id="output" class="box">
    <div class="box" id="demo4">
      <strong>Example 4 - User came from referrer</strong>
      <p class="instructions">
        Fire off the conversion pixel when visitor comes from a particular referrer.

     <!-- Copy this script tag -->
    <script tag="text/javascript">
      // Example 4 - user came from Google/Facebook/Twitter
      window.onload = function() {
      var example4 = {
        initialize: function() {
          var referringURL = document.referrer;

          if (referringURL.match(/^https?:\/\/([^\/]+\.)?google\.com(\/|$)/i)) {
            _pq.push(["track", "User came from Google"]);
            output.log("<hr>Example 4 fired - user came from Google");
          } else if (referringURL.match(/^https?:\/\/([^\/]+\.)?facebook\.com(\/|$)/i)) {
            pq.push(["track", "User came from Facebook"]); 
            output.log("<hr>Example 4 fired - user came from Facebook");
          } else if (referringURL.match(/^https?:\/\/([^\/]+\.)?twitter\.com(\/|$)/i)) {
            _pq.push(["track", "User came from Twitter"]);
            output.log("<hr>Example 4 fired - user came from Twitter");
          } else if (referringURL.match(/^https?:\/\/([^\/]+\.)?uservoice\.com(\/|$)/i)) {
            _pq.push(["track", "User came from Uservoice"]);
            output.log("<hr>Example 4 fired - user came from Uservoice");
          } else {
            output.log("<hr>Example 4 - no referrer");

          var el = document.getElementById("demo4");
 = "#33CC66";



                * {
  font-family: helvetica, arial;  

body {
  background-color: #e4e4e4;

.instructions {
  color: #444;

.box {
  background-color: white;
  padding: 20px;
  border: 1px solid #ccc;
  display: block;
  width: 50%;
  margin-top: 10px;
  border-radius: 4px;
  cursor: pointer;
  text-align: left;

.box:hover {
  background-color: #FFFF99;

#output {
  width: 40%;
  font-family: monospace;
  background-color: #fff;
  margin-left: 20px;


                (function() {
  window._pq = window._pq || [];
  var pa = document.createElement('script'); pa.type = 'text/javascript'; pa.async = true;
  pa.src = ('https:' == document.location.protocol ? 'https:' : 'http:') + "//";
  var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(pa, s);

var output = {
  log: function(txt) {
    var el = document.getElementById("output");
    el.innerHTML = el.innerHTML + txt + "<br>";