Check out example codes for "sockjs-node/info?t=net::ERR_CONNECTION_TIMED_OUT". It will help you in understanding the concepts better.

Code Example 1

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

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