I am using Traefik with entrypoints (a treafik docker container running) to route “sub.mydomain.com” (https://sub.mydomain.com/) to my jitsi running dockers.
The 4 jitsi standard docker containers are connected through “ports” entries in the docker-compose.yml, except the web container/service with “expose” instead of “ports” (since the traefik container has ports 80 and 443).
All container are in one network, created with the traefik container.
I am using the docker jitsi image version: stable-9457-2.
The Jitsi Meet welcome page is reachable. I cannot start a new session, it kicks me out at once. Through starting in Linux Terminal (docker compose -f jitsi-docker-compose.yml up -d), I got the following error visible in my Chrome browser development console on the other “testing access” machine:

<Pa.connectionHandler>:  (TIME) Strophe connecting:  3901.5999999996275
strophe.stream-management.js:224 WebSocket connection to 'wss://meet.mydomain.com/xmpp-websocket?room=test' failed: 
_connect @ strophe.umd.js:5779
...
connect @ xmpp.js:685
Bh.connect @ JitsiConnection.js:72
...
strophe.util.js:84 2024-05-12T19:27:04.287Z [modules/xmpp/strophe.util.js] <Pa.St.Strophe.log>:  Strophe: Websocket error {"isTrusted":true} Websocket error {"isTrusted":true}
...
socket.onerror @ strophe.umd.js:5783
error (async)
...
xmpp.js:292 2024-05-12T19:27:04.288Z [modules/xmpp/xmpp.js] <Pa.connectionHandler>:  (TIME) Strophe connfail[The WebSocket connection could not be established or was disconnected.]:    3934.800000000745
strophe.util.js:84 2024-05-12T19:27:04.288Z [modules/xmpp/strophe.util.js] <Pa.St.Strophe.log>:  Strophe: Websocket closed unexcectedly Websocket closed unexcectedly

There is a thread in this forum but I started one new, because I have another setup.
And my error seems related WSS websocket both, the xmpp websocket and the colibri websocket, the WSS connection primarily.

I would post my yml files, but before I would like to know if I should post them completely with all the config tries made and commnted out, or just the running config.

By the way, to which Jitsi component does the wss connection go? Web, Prosody. Jicofo or JVB?

Until now, I solved server errors existing beneath the broken wss connection. Most of them DNS or URL related. See at: https://community.jitsi.org/t/jitsi-meet-docker-compose-setup-with-traefik-dns-error/131556