Parsedown::sanitiseElement( $Element )

    protected function sanitiseElement(array $Element)
    {
        static $goodAttribute = '/^[a-zA-Z0-9][a-zA-Z0-9-_]*+$/';
        static $safeUrlNameToAtt  = array(
            'a'   => 'href',
            'img' => 'src',
        );

        if ( ! isset($Element['name']))
        {
            unset($Element['attributes']);
            return $Element;
        }

        if (isset($safeUrlNameToAtt[$Element['name']]))
        {
            $Element = $this->filterUnsafeUrlInAttribute($Element, $safeUrlNameToAtt[$Element['name']]);
        }

        if ( ! empty($Element['attributes']))
        {
            foreach ($Element['attributes'] as $att => $val)
            {
                # filter out badly parsed attribute
                if ( ! preg_match($goodAttribute, $att))
                {
                    unset($Element['attributes'][$att]);
                }
                # dump onevent attribute
                elseif (self::striAtStart($att, 'on'))
                {
                    unset($Element['attributes'][$att]);
                }
            }
        }

        return $Element;
    }