diff --git a/docker-compose.yml-example b/docker-compose.yml-example
index 302ec6b..63c2acc 100644
--- a/docker-compose.yml-example
+++ b/docker-compose.yml-example
@@ -164,6 +164,7 @@ services:
       - KCCONF_SERVER_SSLKEYS_PATH=/kopano/ssl/clients
       - KCCONF_SERVER_PROXY_HEADER=* # delete line if webapp is not behind reverse proxy
       - KCCONF_SERVER_SYSTEM_EMAIL_ADDRESS=${POSTMASTER_ADDRESS}
+      - KCCONF_SERVER_SYNC_GAB_REALTIME=no
       - KCCONF_LDAP_LDAP_URI=${LDAP_SERVER}
       - KCCONF_LDAP_LDAP_BIND_USER=${LDAP_BIND_DN}
       - KCCONF_LDAP_LDAP_BIND_PASSWD=${LDAP_BIND_PW}