} else {
                        logger.warn("id is empty: {}", memberOf);
                    }
                    final String[] names = fessConfig.getEntraIdPermissionFields();
                    final boolean useDomainServices = fessConfig.isEntraIdUseDomainServices();
                    for (final String name : names) {

     * Uses new entraid.permission.fields key with fallback to legacy aad.permission.fields.
     * @return Array of permission field names.
     */
    default String[] getEntraIdPermissionFields() {
        String value = getSystemProperty("entraid.permission.fields", null);
        if (StringUtil.isBlank(value)) {
            value = getSystemProperty("aad.permission.fields", "mail");
        }