PMA\libraries\config\FormDisplay::_setComments PHP Method

    private function _setComments($system_path, array &$opts)
    {
        // RecodingEngine - mark unavailable types
        if ($system_path == 'RecodingEngine') {
            $comment = '';
            if (!function_exists('iconv')) {
                $opts['values']['iconv'] .= ' (' . __('unavailable') . ')';
                $comment = sprintf(__('"%s" requires %s extension'), 'iconv', 'iconv');
            }
            if (!function_exists('recode_string')) {
                $opts['values']['recode'] .= ' (' . __('unavailable') . ')';
                $comment .= ($comment ? ", " : '') . sprintf(__('"%s" requires %s extension'), 'recode', 'recode');
            }
            if (!function_exists('mb_convert_encoding')) {
                $opts['values']['mb'] .= ' (' . __('unavailable') . ')';
                $comment .= ($comment ? ", " : '') . sprintf(__('"%s" requires %s extension'), 'mb', 'mbstring');
            }
            $opts['comment'] = $comment;
            $opts['comment_warning'] = true;
        }
        // ZipDump, GZipDump, BZipDump - check function availability
        if ($system_path == 'ZipDump' || $system_path == 'GZipDump' || $system_path == 'BZipDump') {
            $comment = '';
            $funcs = array('ZipDump' => array('zip_open', 'gzcompress'), 'GZipDump' => array('gzopen', 'gzencode'), 'BZipDump' => array('bzopen', 'bzcompress'));
            if (!function_exists($funcs[$system_path][0])) {
                $comment = sprintf(__('Compressed import will not work due to missing function %s.'), $funcs[$system_path][0]);
            }
            if (!function_exists($funcs[$system_path][1])) {
                $comment .= ($comment ? '; ' : '') . sprintf(__('Compressed export will not work due to missing function %s.'), $funcs[$system_path][1]);
            }
            $opts['comment'] = $comment;
            $opts['comment_warning'] = true;
        }
        if (!defined('PMA_SETUP')) {
            if ($system_path == 'MaxDbList' || $system_path == 'MaxTableList' || $system_path == 'QueryHistoryMax') {
                $opts['comment'] = sprintf(__('maximum %s'), $GLOBALS['cfg'][$system_path]);
            }
        }
    }