Websocket upgrade never works/Connecting via Websocket

[fkrauthan]

I recently attached the latest socket.io version (4.5.3) to a keystone server via the exposed extendHttpServer hook. The only setting I set on my socket.io server itself is CORS for a second localhost domain (my test client).

Socket.IO itself works fine as in the polling transport works exactly as expected. However, it never upgrades to websocket. When I force websockets it never connects and I see WebSocket is closed before the connection is established. in the chrome developer tools.

The code that creates the HTTP server and calls that hook can be found here. However I didn't see anything strange in terms of settings that could cause this.

Anyone any ideas on how I can troubleshoot this further to figure out why the websockets part is not working?

[fkrauthan]

Actually never mind. After a PC restart, it all works as expected. No clue what was going on but no code changes were required. This can be removed.