final String name = fessConfig.getQueryBrowserLangParameterName();
        if (StringUtil.isNotBlank(name)) {
            try {
                return requestManager.getParameter(name).filter(StringUtil::isNotBlank).map(LocaleUtils::toLocale);
            } catch (final Exception e) {
                logger.debug("Failed to parse a value of {}.", name, e);
            }
        }