<!DOCTYPE html>
<html>
 <head>
  <meta charset="utf-8">
  <title>
   center25.html - center tag on table
  </title>
  <style>
  strong { color: red }
  </style>
 </head>
 <body>
 <center>
 <table>
 <tr><td>Table centered by &lt;center&gt;</td></tr>
 </table>
 </center>
 <p>This file contains <strong>&lt;center;&gt; ... &lt;/center;&gt;</strong>
</p>
 <p>The 'experimental' Nu Markup Checker flags this as an <strong>HTML5 ERROR</strong> with the string <strong>
  &quot;Error: The center element is obsolete. Use CSS instead.&quot;</strong>
 </p>

 <p>If 'clean' at present tidy 'silently' replaces this with a &lt;div class=&quot;c1&quot;&gt;, and 
  add the CSS in TY_(CleanDocument)(doc), ...
 </p>

 <p>Q: <strong>Should this behaviour be modified?</strong>
 </p>
 <p>A: There are various possibilities<br>
  <ul>
   <li>If the document is configured (or found?) to be HTML5, then
     <ul>
      <li>If clean configured
  	<ul>
   		<li>Fix it silently, <strong>as now</strong>
   		<li>Fix it with a warning
		<li>No fix and flag as an error, like the validator
        </ul>
      <li>Clean not configured
  	<ul>
   		<li>No fix, with no warning or error, <strong>as now</strong>
   		<li>Fix it with a warning
		<li>No fix and flag as an error, like the validator
        </ul>
     </ul>
   <li>Else if NOT configured (or found?) to be HTML5
     <ul>
      <li>If clean configured
  	<ul>
   		<li>Fix it silently, <strong>as now</strong>
   		<li>Fix it with a warning
        </ul>
      <li>Clean not configured
  	<ul>
   		<li>Flag as a warning
		<li>Flag as an error
		<li>No warning or error, <strong>as now</strong>
        </ul>
     </ul>
  </ul>
  
  <p>Also perhaps Tidy5 needs another configuration parameter as suggested by the validator.w3.org,
  namely <strong>&quot;HTML4-specific tokenization errors are enabled.&quot;</strong> That is being 
  able to clearly inform tidy that is the document is to be taken as HTML5, then certain
  tags are to be an error.
  </p>
 </body>
</html>