Some apps that have virtual attributes, will get a warning during the startup if they are converted from Mx 4.
Warning: EventAdmin: Exception during event dispatch [org.osgi.service.event.Event [topic=com/mendix/events/runtime/beforeRunning] | [org.osgi.service.event.EventHandler] | Bundle(webui [84])] (bundle: webui, service: [org.osgi.service.event.EventHandler])
Our Expert Services dept. offers the workaround below: