webpack.config.js

const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const TerserJSPlugin = require('terser-webpack-plugin');
const OptimizeCSSAssetsPlugin = require('optimize-css-assets-webpack-plugin');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const path = require('path');

module.exports = {
  entry: {
    main: './UI/index.html',
    error: './UI/error.html'
  },
  plugins: [new MiniCssExtractPlugin(), new HtmlWebpackPlugin()],
  optimization: {
    minimizer: [new TerserJSPlugin({}), new OptimizeCSSAssetsPlugin({})],
  },
  module: {
    rules: [
      {
        test: /\.html$/i,
        loader: 'html-loader',
      },
      {
        test: /\.css$/i,
        use: [MiniCssExtractPlugin.loader, 'css-loader'],
      },
      {
        test: /\.(png|jpe?g|gif)$/i,
        use: [
          {
            loader: 'file-loader'
          }
        ],
      },
    ]
  },
  output: {
    path: path.resolve(__dirname, 'dist'),
  }
}