I've floated this problem a while ago, but I only just got around to actually getting some data on it.
It seems like websocket handling ... well, for lack of a better word, "broke" after v9.4.12.v20180830.
I'm using the Ninja Framework, which bundles this version of Jetty as its internal webserver, and if I launch a skeleton WS server using the bundled Jetty instance, connections go through just fine. On the other hand, if I use the latest Jetty plugin from Maven Central, and launch the same WS server, I get an error when I try to send a message, specifically,
org.java_websocket.exceptions.InvalidFrameException: bad rsv RSV1: true RSV2: false RSV3: false. I'm using
this project as my WS client.
Now, my go-to reaction would be to simply downgrade my standalone Jetty installation to 9.4.12, but unfortunately because my real application runs under Java 11, I cannot do that (due to an outdated ASM in the 9.4.12 version).
Can anyone give me some pointers as where this might be going wrong?
Best,
Zalan