You can increase message size by using max_frame_Size.

Sample:

async fn handle_ws(req: HttpRequest, stream: web::Payload) -> Result<HttpResponse, Error> {
    let (res, session, msg_stream) = actix_ws::handle(&req, stream)?;
    let msg_stream = msg_stream.max_frame_size(1024 * 1024 * 10);
}