The WildFlyConfigurationFactory was introduced to have a customized ConfigurationFactory. During deploy, this is not accessed if the JaxrsDeploymentMarker.isJaxrsDeployment(deploymentUnit) returns false. However, in undeploy that check is not done which may cause resources to be created and/or loaded from a ServiceLoader during shutdown. We need to check if the deployment is a REST deployment before attempting to unregister the deployment.