title: Disable HTML stack traces by Xdebug
body: <p>The administrator has installed Xdebug 2.1.1 in our shared PHP 5.3.0 server in order to use its debugger. Now, I can hardly read the stack traces of uncatched exceptions because they are formatted by Xdebug with annoying colours that interact badly with the site's CSS:</p>
  
  <p><img src="https://i.stack.imgur.com/NHVRi.png" alt="Unreadable stack trace"></p>
  
  <p>Since PHP runs as Apache module, I've tried to disable this feature in an <code>.htaccess</code> file but I can't make it go:</p>
  
  <pre><code>php_flag xdebug.default_enable Off
  php_flag xdebug.overload_var_dump Off
  php_flag xdebug.show_exception_trace Off
  php_value xdebug.trace_format 1
  </code></pre>
  
  <p><code>phpinfo()</code> shows my changes in the <em>Local Value</em> column but I can still see those horrible orange tables. What's the directive I need to change?</p>