WebSocketNotificationService is loaded in Business Central, however it is overwritten in WebSocketKieServerMgmtControllerImpl [1] by org.kie.workbench.common.screens.server.management.backend.service.NotificationServiceCDI. Therefore WebSocketEventHandler in KieServerControllerClient doesn't work.

Would it have sense to alter the implementation to allow several notification services to take care of notify events?

[1] https://github.com/kiegroup/droolsjbpm-integration/blob/4ca6d23c2a8361e5866ba950ad7613ee64ad80ee/kie-server-parent/kie-server-controller/kie-server-controller-websocket/src/main/java/org/kie/server/controller/websocket/management/WebSocketKieServerMgmtControllerImpl.java#L62