SSE integration in CDI abruptly fails with no indication why

https://lists.apache.org/thread.html/10d99c0d013a3d23361a3898171e7bd2b311a509349433db3b6cacaa@%3Cusers.cxf.apache.org%3E has more details

Intermittently, when bootstrapping CXF + CDI, the integration for SSE will fail. When it fails, there's no log messages indicating the issue, however attempts to invoke any rest endpoint will give a warning like:

Sep 17, 2017 7:50:33 PM org.apache.cxf.transport.servlet.ServletController
invoke
WARNING: Can't find the request for http://my-hostname:4403/rest's Observer