 <p>CML files get rendered as XML from the server because the server is telling Chrome it is XML with header <code>Content-Type:application/xml</code>. When a local file is opened there is no <code>Content-Type</code> header so Chrome guesses off of the file extension and in this case is not aware of CML. You could open a feature request for Chrome to read CML files as XML but I don't know if they will implement it: <a href="http://new.crbug.com" rel="nofollow">http://new.crbug.com</a></p>