Using Websocket server with Bearer token

[EvilWatermelon]

Hi,

I wrote an HTTP(S) endpoint using actix-web which will be upgraded to a websocket connection. I'm also using JWT for authorization. How can I pass the Bearer token as a client? As far as I have read I'm not allowed to add a new header value. Is there something like socket.io that runs in background because socket.io is able to pass the Bearer token.