fix: re-add minification

Author: afriestad

config/webpack.config.prod.js

@@ -11,6 +11,8 @@ const InterpolateHtmlPlugin = require('react-dev-utils/InterpolateHtmlPlugin');
 const SWPrecacheWebpackPlugin = require('sw-precache-webpack-plugin');
 const paths = require('../config/paths');
 const getClientEnvironment = require('./env');
+const OptimizeCSSAssetsPlugin = require('optimize-css-assets-webpack-plugin');
+const safePostCssParser = require('postcss-safe-parser');
 
 // Webpack uses `publicPath` to determine where the app is being served from.
 // It requires a trailing slash, or the file assets will get an incorrect path.
@@ -107,6 +109,20 @@ module.exports = {
         // Enable file caching
         cache: true,
         sourceMap: shouldUseSourceMap
+      }),
+      new OptimizeCSSAssetsPlugin({
+        cssProcesorOptions: {
+          parser: safePostCssParser,
+          map: shouldUseSourceMap
+            ? {
+                // This forces the sourcemap to be output into a separate file
+                inline: false,
+                // This appends the sourceMappingURL to the end of the css file,
+                // helping the browser find the sourcemap
+                annotation: true
+              }
+            : false
+        }
       })
     ],
     // Automatically split vendor and commons

package.json

@@ -44,6 +44,7 @@
     "http-proxy-middleware": "^0.20.0",
     "mini-css-extract-plugin": "^0.4.0",
     "minimist": "1.2.0",
+    "optimize-css-assets-webpack-plugin": "^5.0.3",
     "postcss-flexbugs-fixes": "^3.3.0",
     "postcss-loader": "2.1.5",
     "promise": "8.0.1",