Upgrade webpack, replace OptimizeCssAssetsPlugin with CssMinimizerPlugin

package.json

@@ -29,7 +29,7 @@
     "mock:pagerduty_api": "mockserver -m test/mocks",
     "build": "webpack --config webpack.dev.js",
     "build:watch": "webpack --watch --config webpack.dev.js",
-    "build:prod": "NODE_ENV=production webpack --config webpack.prod.js --display-modules",
+    "build:prod": "NODE_ENV=production webpack --config webpack.prod.js",
     "app": "node -r esm src/pagerbeauty.js",
     "app:watch": "nodemon -r esm src/pagerbeauty.js",
     "app:prod": "NODE_ENV=production node -r esm src/pagerbeauty.js",
@@ -65,6 +65,7 @@
     "conventional-changelog-ember": "^2.0.9",
     "core-js": "3",
     "css-loader": "^5.2.4",
+    "css-minimizer-webpack-plugin": "^2.0.0",
     "eslint": "^7.25.0",
     "eslint-config-airbnb": "^18.2.1",
     "eslint-config-airbnb-base": "^14.2.1",
@@ -78,7 +79,6 @@
     "node-sass": "^4.12.0",
     "nodemon": "^2.0.7",
     "nyc": "^15.0.0",
-    "optimize-css-assets-webpack-plugin": "^5.0.4",
     "prop-types": "^15.7.2",
     "puppeteer-core": "5.0.0",
     "react": "^17.0.2",
@@ -89,8 +89,8 @@
     "sinon-chai": "^3.6.0",
     "style-loader": "^2.0.0",
     "tap-xunit": "^2.4.1",
-    "webpack": "^4.33.0",
-    "webpack-cli": "^3.3.3",
+    "webpack": "^5.36.2",
+    "webpack-cli": "^4.6.0",
     "webpack-merge": "^5.7.3"
   },
   "nodemonConfig": {

webpack.prod.js

@@ -1,18 +1,29 @@
 /* eslint-disable import/no-extraneous-dependencies */
 const { merge } = require('webpack-merge');
-const OptimizeCssAssetsPlugin = require('optimize-css-assets-webpack-plugin');
+const CssMinimizerPlugin = require('css-minimizer-webpack-plugin');
+const TerserPlugin = require('terser-webpack-plugin');
 /* eslint-enable */
 const common = require('./webpack.common.js');
 
 module.exports = merge(common, {
   mode: 'production',
-  plugins: [
-    new OptimizeCssAssetsPlugin({
-      cssProcessorPluginOptions: {
-        preset: ['default', { discardComments: { removeAll: true } }],
-      },
-    }),
-  ],
+  optimization: {
+    minimizer: [
+      new TerserPlugin({
+        extractComments: false,
+      }),
+      new CssMinimizerPlugin({
+        minimizerOptions: {
+          preset: [
+            'default',
+            {
+              discardComments: { removeAll: true },
+            },
+          ],
+        },
+      }),
+    ],
+  },
   output: {
     path: `${__dirname}/assets/dist-prod`,
   },