final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final String name = fessConfig.getQueryBrowserLangParameterName();
        if (StringUtil.isNotBlank(name)) {
            try {
                return requestManager.getParameter(name).filter(StringUtil::isNotBlank).map(LocaleUtils::toLocale);

     * The value is, e.g. browser_lang <br>
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getQueryBrowserLangParameterName();

    /**
     * Get the value for the key 'query.replace.term.with.prefix.query'. <br>
     * The value is, e.g. true <br>