That may sound surprising and even counter-intuitive, but for a some of your users, your Analytics implementation might be breaking your website.

gistfile1.md

Your Analytics might be Breaking your Website.

googleAnalyticsOutboundLinkTracking.html

<script type="text/javascript">
/**
 * Function that tracks a click on an outbound link in Google Analytics.
 * This function takes a valid URL string as an argument, and uses that URL string
 * as the event label.
 */
var trackOutboundLink = function (url) {
   ga('send', 'event', 'outbound', 'click', url, {
      'hitCallback': function () {
         document.location = url;
      }
   });
}
</script>

<a href="http://www.example.com" onclick="trackOutboundLink('http://www.example.com'); return false;">
   Check out example.com
</a>

googleAnalyticsOutboundLinkTrackingFixed.js

/**!
 * Function that tracks a click on an outbound link in Google Analytics.
 * This function takes a valid URL string as an argument, and uses that URL string as the 
 * event label.
 *
 * In the case where the "analytics.js" library is not loaded (either because the event
 * was triggered too early in the page lifecycle or because the library was blocked by an
 * extension), redirect the user to the intended destination.
 *
 * @param {String} url The URL to navigate to after recording a Custom Event in Analytics.
 * @return {void}
 *
 * @author Philippe Sawicki (http://philippesawicki.com)
 * @copyright Copyright 2015 Philippe Sawicki (http://philippesawicki.com)
 */
var trackOutboundLink = function (url) {
   if (ga.q) {
      // Analytics has not loaded yet or was blocked:
      window.location = url;
   } else {
      ga('send', 'event', 'outbound', 'click', url, {
         'hitCallback': function () {
            window.location = url;
         }
      });
   }
}

googleAnalyticsOutboundLinkTrackingWithCSS.html

<script type="text/javascript">
/**!
 * Prevents Analytics implementation from breaking site features due to user-installed
 * extensions like Ghostery.
 *
 * @author Philippe Sawicki (http://philippesawicki.com)
 * @copyright Copyright 2015 Philippe Sawicki (http://philippesawicki.com)
 */
(function ($) {
   if (typeof $ !== 'undefined') {
      $('.js-ga-outbound-link').on('click', function (event) {
         if (!ga.q) {
            event.preventDefault();
            
            var destinationLink = $(this).attr('href');
            ga('send', 'event', 'outbound', 'click', destinationLink, {
               'hitCallback': function () {
                  window.location = destinationLink;
               }
            });
         }
      }
   }
})(jQuery);
</script>
 
<a href="http://www.example.com" class="js-ga-outbound-link">
   Check out example.com
</a>