Basically adding to or removing from restClass as the TomEEMicroProfileListener is currently doing has no effect on REST applications that "extend Application" and provide getClasses() or getSingletons(). Even if the OpenAPIFilter is in the providers, the endpoint is not added so no /openapi endpoint exists.
When the request for /openapi comes through there is no OpenAPIFilter loaded (but the opentracing filter is loaded). So the OpenAPIFilter does not exist to handle the request. Did you manage to get to look at the CDI-Embedded? -- Sent from: http://tomee-openejb.979440.n4.nabble.com/TomEE-Dev-f982480.html