title: HTML Purifier - Change default allowed HTML tags configuration
body: <p>I want to allow a <strong>limited</strong> white list of HTML tags that users can use in my forum. So I have configured the HTML Purifier like so:</p>
  
  <pre><code>$config = HTMLPurifier_Config::createDefault();
  $config-&gt;set('HTML.Allowed', 'p,a[href|rel|target|title],img[src],span[style],strong,em,ul,ol,li');
  $purifier = new HTMLPurifier($config);
  </code></pre>
  
  <p>What I am wondering is, does the default configuration of the HTML Purifier still apply, with the exception of a reduced number of accepted HTML tags <em>or</em> do I need to re-set every possible configuration parameter manually? </p>
  
  <p>Additionally, should I tweak the default configuration in any way to stay safe? I am new to the whole XSS protection thing, new to HTML Purifier and didn't find that the manual gave a lot of 'basic' tips and hints.</p>