webpack.config.js

const HtmlWebPackPlugin = require('html-webpack-plugin');
const CopyPlugin = require('copy-webpack-plugin');
const path = require('path');

module.exports = {
  devServer: {
    contentBase: path.join(__dirname, 'dist'),
    compress: false,
    port: 9000,
  },
  entry: {
    main: './src/index.js',
    background: './src/background/background.js',
  },
  module: {
    rules: [
      {
        test: /\.(js|jsx)$/,
        exclude: /node_modules/,
        use: {
          loader: 'babel-loader',
        },
      },
      {
        test: /\.css$/i,
        use: ['style-loader', 'css-loader', 'postcss-loader'],
      },
      {
        test: /\.html$/,
        use: [
          {
            loader: 'html-loader',
          },
        ],
      },
    ],
  },
  plugins: [
    new HtmlWebPackPlugin({
      template: './src/index.html',
      filename: './index.html',
      excludeChunks: ['background'],
    }),
    new CopyPlugin({
      patterns: [
        { from: 'src/icons', to: 'icons' },
        { from: 'src/manifest.json', to: '' },
      ],
    }),
  ],
};