title: Firefox event.clientX not functioning
body: <p>I'm working on a d3 and js project.</p>
  
  <p>The beginning of the function looks like:</p>
  
  <pre><code>$(document).ready(function() { 
      d3.select("#aid").select(".abutton").on("mousemove",function() {
          afile.style("top", (event.clientY+10)+"px").style("left",(event.clientX+15)+"px");
          afile.html("&lt;h3&gt;Click text here&lt;/p&gt;&lt;p&gt;or here&lt;/p&gt;");
      }); 
  </code></pre>
  
  <p>I've done quite a bit of Googling!</p>
  
  <p>The essence is that on <a href="http://api.jquery.com/mousemove/" rel="nofollow noreferrer">mouseover</a>, it should do the function. This works in Chrome and IE because the event variable is global, and as such so are it's client* properties.</p>
  
  <p>The solution, as I understand it, is to pass in an <code>eventObject</code>. When I do that, my code looks like:</p>
  
  <pre><code>$(document).ready(function() { 
      d3.select("#aid").select(".abutton").on("mousemove",function(event) {
          afile.style("top", (event.clientY+10)+"px").style("left",(event.clientX+15)+"px");
          afile.html("&lt;h3&gt;Click text here&lt;/p&gt;&lt;p&gt;or here&lt;/p&gt;");
      });
  </code></pre>
  
  <p>The Firefox log gives me:</p>
  
  <blockquote>
    <p>[09:59:04.308] TypeError: event is undefined @ filepathofjavascriptfile</p>
  </blockquote>
  
  <p>and similarly, it breaks in Chrome:</p>
  
  <blockquote>
    <p>Uncaught TypeError: Cannot read property 'clientY' of undefined filepathofjavascriptfile
    (anonymous function) help.js:34</p>
  </blockquote>
  
  <p>What am I doing wrong? Please let me know if you need anything else.</p>