bug: double javascript

In the instructions you say to add the following javascript before </head> :

However the plugin via the Sender_Automated_Emails.php file automatically writes the script

    echo "
        <script>
          (function (s, e, n, d, er) {
            s['Sender'] = er;
            s[er] = s[er] || function () {
              (s[er].q = s[er].q || []).push(arguments)
            }, s[er].l = 1 * new Date();
            var a = e.createElement(n),
                m = e.getElementsByTagName(n)[0];
            a.async = 1;
            a.src = d;
            m.parentNode.insertBefore(a, m)
          })(window, document, 'script', 'https://cdn.sender.net/accounts_resources/universal.js', 'sender');
          sender('{$key}');
        </script>
        ";

So this is a duplicate of the instructions. Furthermore, displaying the div with the script already injected into the </head> tag does not work. We therefore recommend removing the echo in Sender_Automated_Emails.php and adding the javascript directly to a widget