title: How to keep my non-breaking spaces with HTML Tidy (PHP)?
body: <p>I've just noticed that <code>tidy_repair_string()</code> is removing my non-breaking spaces from empty elements causing my table to collapse.  Basically I've put in:</p>
  
  <blockquote>
    <p><code>&lt;td&gt;&amp;nbsp;&lt;/td&gt;</code></p>
  </blockquote>
  
  <p>and HTML Tidy is stripping them out to:</p>
  
  <pre><code>&lt;td&gt; &lt;/td&gt;
  </code></pre>
  
  <p>which may or may not be some Unicode break but either way it's collapsing.  The only <code>&amp;nbsp;</code> related option I've seen is 'quote-nbsp' but that doesn't seem to be it.  I think it defaults to on anyway.</p>
  
  <p>How do I keep my non-breaking spaces?</p>