UIServiceInitListener not exceuted on jetty server

When running the jetty server with the maven plugin “jetty-maven-plugin” the service gets executed and loaded. But when building the WAR file to place inside webapps folder and the running the jetty server via java -jar start.jar the service does not get executed.

I’m using Vaadin 13 and jetty (jetty-distribution-9.4.18.v20190429)