title: tooltip jqueryUI css issue
body: <p>I have an issue about jqueryUI tooltip..</p>
  
  <p>In fact, impossible to change the css style of the class .ul-tooltip. .
  specially on firefox. </p>
  
  <p>In more, even on the offical website.. On the demo : <a href="https://jqueryui.com/tooltip/#custom-style" rel="nofollow">https://jqueryui.com/tooltip/#custom-style</a></p>
  
  <p>When I look the style on firefox and on chrome, the style are different. </p>
  
  <p>I try to override the css </p>
  
  <pre><code>.ui-tooltip {
    background: #fcfcfa !important;
    color: #86c724 !important;
    border: 1px solid #86c724 !important;
    border-radius: 5px !important;
    -moz-border-radius: 5px !important;
    padding: 10px !important;
    -webkit-box-shadow: 0 0 5px  rgba(0,0,0,0.25);
            box-shadow: 0 0 5px  rgba(0,0,0,0.25);
  }
  </code></pre>
  
  <p>but no result. </p>
  
  <p>I try to add a new class and manage style by it.. no result</p>
  
  <pre><code>  &lt;script&gt;
    $(function() {
      $( ".infoboxcontainer" ).tooltip({
        tooltipClass: "myNewClass"
      });
  
    });
    &lt;/script&gt;
  </code></pre>
  
  <p>No idea what happen.. it's like if firefox add is own css for tooltip. </p>