title: DOMPDF generating blank pdf
body: <p>I am using DOMPDF library 0.6.0 beta 3 to generate pdf files using PHP. Some of my html can be processed to PDF correctly and some not. Below is an example of one which can not. I have validated my html via w3c html validator. What can I do to resolve this issue?</p>
  
  <pre><code>&lt;?php
    require_once("dompdf/dompdf_config.inc.php");
      $html = "&lt;!DOCTYPE html&gt;
              &lt;html&gt;
                &lt;head&gt;
                &lt;title&gt;&lt;/title&gt;
                        &lt;meta http-equiv='Content-Type' content='text/html; charset=utf-8'/&gt;
                &lt;/head&gt;
               &lt;body&gt;
                   &lt;p&gt;Algarve Bird Watching Festival About to Begin&lt;/p&gt;
                   &lt;p&gt;&lt;span style='font-family:calibri;font-size:11pt'&gt;&amp;nbsp;&lt;/span&gt;&lt;/p&gt;
                   &lt;p&gt;Test Title&lt;/p&gt;
                   &lt;p&gt;Lorem ipsum sit dolor amet&lt;sup&gt;th&lt;/sup&gt; Lorem ipsum sit dolor amet &lt;/p&gt;
                   &lt;p&gt;Lorem ipsum sit dolor amet&lt;/p&gt;
                   &lt;p&gt;Lorem ipsum sit dolor amet &lt;/p&gt;
                   &lt;p&gt;Lorem ipsum sit dolor amet &lt;a href='http://www.test.com'&gt;test&lt;/a&gt;
                    Lorem ipsum sit dolor amet &amp;nbsp; 
                    &lt;/p&gt;
      &lt;p&gt;&lt;span style='font-family:calibri;font-size:11pt'&gt;&amp;nbsp;&lt;/span&gt;&lt;/p&gt;
               &lt;/body&gt;
               &lt;/html&gt;";
  
      $dompdf = new DOMPDF();
      $dompdf-&gt;load_html($html);
      $dompdf-&gt;set_paper("a4", "portrait");
      $dompdf-&gt;render();
      $dompdf-&gt;stream();
  ?&gt;
  </code></pre>