I found that bug you were looking for. I added a paragraph tag through clip, then I pressed the control period. It inserted the </p>. Then I switched to book view and got the red warning in book view about the tags not matching. It appears that an extra </p> tag got inserted just above </body> when I pressed control period. I eliminated that and it went away.
This is the section in question.
<p class="capt">THE AIR PLAN FOR THE LANDINGS IN NORMANDY, 6 JUNE 1944</p> <!-- Mirrored from http://www.ibiblio.org/hyperwar/UN/U...RAF-III-5.html
by HTTrack Website Copier/3.x [XR&CO'2010], Wed, 26 Sep 2012 11:59:12 GMT --><!-- Added by HTTrack --><!-- /Added by HTTrack -->(extra /p tag was here.)