webpack.demo.js

const webpack = require('webpack');
const merge = require('webpack-merge');
const Dotenv = require('dotenv-webpack');
const CopyWebpackPlugin = require('copy-webpack-plugin');
const common = require('./webpack.common.js');

module.exports = (env) => {
  const commonConfig = common(env);

  return merge(commonConfig, {
    mode: 'development',
    devtool: 'source-map',
    plugins: [
      ...commonConfig.plugins,
      new CopyWebpackPlugin([
        { from: 'icon16.png', to: 'icon16.png' },
        { from: 'icon48.png', to: 'icon48.png' },
        { from: 'icon128.png', to: 'icon128.png' },
        { from: 'content.js', to: 'content.js' },
        { from: 'staging.manifest.json', to: 'manifest.json' },
      ]),
      new webpack.optimize.LimitChunkCountPlugin({
        maxChunks: 1,
      }),
      new Dotenv({
        path: './.env.demo',
      }),
    ],
  });
};