// Allowed protocols in link URLs; HTTP protocols always are accepted
$a->config['system']['allowed_link_protocols'] = array('ftp', 'ftps', 'mailto', 'cid', 'gopher');
// Allowed protocols in link URLs; HTTP protocols always are accepted
$a->config['system']['allowed_link_protocols'] = array('ftp', 'ftps', 'mailto', 'cid', 'gopher');