public function getBrowserLanguages($accept_langs = [])
    {
        user_error(__CLASS__ . '::' . __FUNCTION__ . '() is deprecated since Grav 1.6, no longer used', E_USER_DEPRECATED);

        if (empty($this->http_accept_language)) {
            if (empty($accept_langs) && isset($_SERVER['HTTP_ACCEPT_LANGUAGE'])) {
                $accept_langs = $_SERVER['HTTP_ACCEPT_LANGUAGE'];
            } else {
                return $accept_langs;
            }

            $langs = [];

            foreach (explode(',', $accept_langs) as $k => $pref) {
                // split $pref again by ';q='
                // and decorate the language entries by inverted position
                if (false !== ($i = strpos($pref, ';q='))) {
                    $langs[substr($pref, 0, $i)] = [(float)substr($pref, $i + 3), -$k];
                } else {
                    $langs[$pref] = [1, -$k];
                }
            }
            arsort($langs);

            // no need to undecorate, because we're only interested in the keys
            $this->http_accept_language = array_keys($langs);
        }
        return $this->http_accept_language;
    }