sockjs.js:1606 GET http://localhost:8081/sockjs-node/info?t=1608391870249 net::ERR_CONNECTION_REFUSE code example

Example: sockjs-node/info?t=net::ERR_CONNECTION_TIMED_OUT

module.exports = {
    devServer: {
        disableHostCheck: true,
        port: 4000,
        public: '0.0.0.0:4000'
    },
    publicPath: "/"
}