	public function strip_tags($input, $encode = TRUE)
	{
		require_once APPPATH.'libraries/htmlpurifier/HTMLPurifier.auto.php';

		$config = HTMLPurifier_Config::createDefault();
		// Defaults to UTF-8
		// $config->set('Core.Encoding', 'UTF-8');
		// $config->set('HTML.Doctype', 'XHTML 1.0 Transitional');
		$config->set('Core.EnableIDNA', TRUE);
		$config->set('HTML.Allowed', "");
		
		$purifier = new HTMLPurifier($config);
		$clean_html = $purifier->purify($input);

		return $encode ? self::escape($clean_html) : $clean_html;
	}
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.