Ads wording

I am using the plugin to create events using the Events Calendar. Upon duplicating an event and then going in to edit the following code has just recently appeared on each duplicated page. What is this about?

<div id="advertisement" style="position: absolute; top: -9999px; left: -9999px; width: 1px; height: 1px; visibility: hidden;"></div>

<div id="ads" style="position: absolute; top: -9999px; left: -9999px; width: 1px; height: 1px; visibility: hidden;"></div>

<div id="adsbox" style="position: absolute; top: -9999px; left: -9999px; width: 1px; height: 1px; visibility: hidden;"></div>

<div id="adnxs" style="position: absolute; top: -9999px; left: -9999px; width: 1px; height: 1px; visibility: hidden;"></div>

<div id="ad-display" style="position: absolute; top: -9999px; left: -9999px; width: 1px; height: 1px; visibility: hidden;"></div>

<div class="adsbygoogle" style="position: absolute; top: -9999px; left: -9999px; width: 1px; height: 1px; visibility: hidden;"></div>

<div class="advertisement" style="position: absolute; top: -9999px; left: -9999px; width: 1px; height: 1px; visibility: hidden;"></div>

<div class="ad-banner" style="position: absolute; top: -9999px; left: -9999px; width: 1px; height: 1px; visibility: hidden;"></div>

<div class="ads" style="position: absolute; top: -9999px; left: -9999px; width: 1px; height: 1px; visibility: hidden;"></div>

The page I need help with: [log in to see the link]