This does not impact all pages but is present on certain cached pages with the following HTML...
<div class="last-modified-bar"> <div id="mw-mf-last-modified" class="truncated-text pre-content post-content"> <a href="/wiki/Special:History/Headings" data-user-name="" data-user-gender="unknown" data-timestamp="1432744316"> Last modified on 27 May 2015, at 16:31 </a> </div> </div>