How to move css-in-js (Styled Components) to an external css files during build using webpack - ReactJS

Question

I am trying to figure out where the CSS files are residing when I build the react project. I am using webpack and I am able to make a single CSS file for all the styles used throughout the project if I use normal CSS. When I use CSS in js using styled component, I am not getting an external CSS file.

webpack.config.js

var path    = require('path');
var hwp     = require('html-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');


module.exports = {
    entry: path.join(__dirname, '/src/index.js'),
    output: {
        filename: 'index.js',
        path: path.join(__dirname, './dist'),
        publicPath : '/'
    },
    module:{
        rules:[{
            exclude: /node_modules/,
            test: /\.js$/,
            loader: 'babel-loader'
    },
    {
        test: /\.css$/i,
        use: [
            {
            loader : MiniCssExtractPlugin.loader,
            options : {
                publicPath: '/public/path/to/',
            },
        }, 
        'css-loader'
    ]
      }
    ]
    },
    devServer: {
        historyApiFallback: true,
      },
    plugins:[
        new hwp({template:path.join(__dirname, '/src/index.html')}),
        new MiniCssExtractPlugin({
            filename : '[name].css',
            chunkFilename : '[id].css',
        })
    ]
}

Contact.js

import React from 'react'
import styled from "styled-components"

const Container = styled.div`
    background-color : red;
`

 function contact() {
    return (
        <Container>
            <h1>
                Welcome to Contacts page
            </h1>
            
        </Container>
    )
}
export default contact

Answer 1

This isn't supported by styled-components at the moment. From a project member -

We don't support static CSS extraction. You can try out emotion which does.

You might not need static CSS extraction actually, because of several reasons:

There's SSR which sends only critical CSS, instead of all static CSS, for the entire page. You don't even need to do SSR, but can use snapshotting (react-snapshot) or generate a static page (gatsby, et al), which basically saves a SSR result to a html.
Static extraction doesn't generate dynamic CSS, which means your page will either appear broken until the JS executes, or you'll need to defer until the JS is loaded
Caching doesn't actually buy you an advantage, because the JS bundles will likely always change in tandem with the extracted CSS
In v3 we will add preprocessing, which will actually a bigger advantage. As part of that we might support an option for static extraction, since the core library that will bring preprocessing will probably also be integrated into emotion, which does support extraction. So it might become an option. Or not 

Source

Emotion has also removed static css extraction

Duplicate of How can I opt for React Styled-Components to generate a physical CSS file?