webpack.config.js

const path      = require('path')

// Plugins
const HtmlWebpackPlugin = require('html-webpack-plugin'),
      HtmlWebpackInlineSourcePlugin = require('html-webpack-inline-source-plugin'),
      WebpackMessages = require('webpack-messages'),
      MiniCssExtractPlugin = require('mini-css-extract-plugin'),
      CopyPlugin = require('copy-webpack-plugin') // added by me



console.clear()

module.exports = (env, argv) => ({
  mode: (argv.mode === 'production') ? 'production' : 'development',

  // This is necessary because Figma's 'eval' works differently than normal eval
  devtool: argv.mode === 'production' ? false : 'inline-source-map',

  stats: false,
  
  entry: {
    main: './src/main.ts',
    ui: './src/ui.js',
  },
  
  output: {
    filename: '[name].js',
    path: path.join(__dirname, 'build'),
  },

  module: {
    rules: [
      // JS and TS
      {
        test: /\.jsx?$/,
        exclude: /node_modules/,
        use: [
          'babel-loader',
        ]
      },
      {
        test: /\.tsx?$/,
        exclude: /node_modules/,
        use: [
          'babel-loader',
          'ts-loader'
        ]
      },
      // CSS and SCSS
      {
        test: /\.s?css$/,
        use: [
          MiniCssExtractPlugin.loader,
          'css-loader',
          'sass-loader',
        ]
      },
    ]
  },

  resolve: {
    extensions: ['.js', '.jsx', '.ts', '.tsx', '.scss', '.html',],
  },

  plugins: [
    new MiniCssExtractPlugin({filename: '[name].css'}),
    new HtmlWebpackPlugin({
      filename: 'ui.html',
      template: './src/ui.html',
      inlineSource: '.(js|css)$',
      chunks: ['ui'],
    }),
    new HtmlWebpackInlineSourcePlugin(),
    new WebpackMessages(),

    // added by me
    new CopyPlugin({ patterns: [{
      from: './src/manifest.json',
      to: './manifest.json',
      transform: (content, path) => {
        try {
          const str = content.toString().replace('__STATE__', (argv.mode === 'production' ? '🚀 PROD' : '⚙️ DEV'))
          return Buffer.from(str)
        } catch (error) {
          console.error(error)
        }
      } 
    }]})
  ],  
})