Hi,

Looks like something is blocking the websocket connection.
Your application still works because when the library detects that it can't use the websocket connection it falls back to http streaming.

Please open this demo, then move your mouse over the S on the top-left of the page. Does it say "over WebSocket" or "over HTTP"? This will tell us if yours is a client or server side issue.

Is there a load balancer and/or reverse proxy in front of your server?
Please check this file, is your environment correctly configured for firefox running over websockets?