/**
     * onBeforeRender handler
     *
     * Adds the prefetch metas
     *
     * @access  public
     * @return null
     */
    function onBeforeRender()
    {
        $doc = JFactory::getDocument();

        if ($doc->getType() == 'html') {
            $doc->addCustomTag('<link rel="dns-prefetch" href="//images-cdn.ecwid.com/">');
            $doc->addCustomTag('<link rel="dns-prefetch" href="//images.ecwid.com/">');
            $doc->addCustomTag('<link rel="dns-prefetch" href="//app.ecwid.com/">');
        }
    }