webpack.config.js

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const CopyWebpackPlugin = require('copy-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');

module.exports = {
  mode: process.env.NODE_ENV === 'production' ? 'production' : 'development',
  devtool: 'cheap-source-map',
  entry: {
    newtab: './src/newtab.tsx',
  },
  output: {
    path: path.resolve(__dirname, 'dist'),
    filename: '[name].js',
    clean: true,
  },
  module: {
    rules: [
      {
        test: /\.tsx?$/,
        use: [
          {
            loader: 'ts-loader',
            options: {
              transpileOnly: true,
            },
          },
        ],
        exclude: /node_modules/,
      },
      {
        test: /\.css$/,
        use: [MiniCssExtractPlugin.loader, 'css-loader', 'postcss-loader'],
      },
    ],
  },
  plugins: [
    new HtmlWebpackPlugin({
      template: './src/newtab.html',
      filename: 'newtab.html',
      chunks: ['newtab'],
    }),
    new MiniCssExtractPlugin({
      filename: 'styles.[contenthash].css',
    }),
    new CopyWebpackPlugin({
      patterns: [
        { from: 'public/manifest.json', to: 'manifest.json' },
        { from: 'public/*.png', to: '[name][ext]' },
      ],
    }),
  ],
  resolve: {
    extensions: ['.tsx', '.ts', '.js'],
    alias: {
      '@': path.resolve(__dirname, 'src'),
    },
  },
  optimization: {
    splitChunks: {
      chunks: 'all',
    },
    minimize: true,
    usedExports: true,
  },
};