message: use style-loader in dev mode until mini-css-extract-plugin is fixed
diff: /* eslint-env node */
  +/* eslint-disable no-unused-vars, no-undef */
  -// eslint-disable-next-line no-unused-vars
  import * as webpack from 'webpack';
  import * as path from 'path';
  import * as HtmlWebpackPlugin from 'html-webpack-plugin';
  @@ -58,7 +58,13 @@ let config: webpack.Configuration = {
  test: /\.s?css$/,
  exclude: /node_modules/,
  use: [
  - MiniCssExtractPlugin.loader,
  + // FIXME: Replace `style-loader` with `MiniCssExtractPlugin` once https://github.com/webpack-contrib/mini-css-extract-plugin/issues/23# is fixed
  + {
  + loader: 'style-loader',
  + options: {
  + sourceMap: true,
  + },
  + },
  { loader: 'cache-loader' },
  { loader: 'thread-loader' },
  {
  @@ -122,6 +128,7 @@ if (NODE_ENV === 'production') {
  config.output.filename = `[name]-bundle.${gitHash()}.min.js`;
  config.output.chunkFilename = `[name]-[chunkhash].${gitHash()}.min.js`;
  extractCSS.filename = `[name]-[chunkhash].${gitHash()}.min.css`;
  + (config.module.rules[2] as webpack.NewUseRule).use[0] = MiniCssExtractPlugin.loader;
  // FIXME(alecmerdler): Causes error in --mode=production due to scope hoisting
  config.optimization.concatenateModules = false;
  config.stats = 'normal';
  