Support IE11 and Edge with default Mirador UMD build

babel.config.js

+/*
+ * babel.config.js used to support a UMD built version of Mirador that is
+ * compatible with IE11 and Edge.
+ */
+
+// eslint-disable-next-line func-names
 module.exports = function (api) {
   api.cache(true);
 
-  const presets = ['@babel/preset-env', '@babel/preset-react'];
+  const presets = [
+    [
+      '@babel/preset-env',
+      {
+        corejs: 3,
+        exclude: ['transform-typeof-symbol'],
+        forceAllTransforms: true,
+        modules: false,
+        useBuiltIns: 'entry',
+      },
+    ],
+    '@babel/preset-react',
+  ];
+
   const plugins = [
+    'babel-plugin-macros',
+    '@babel/plugin-transform-destructuring',
+    [
+      '@babel/plugin-proposal-class-properties',
+      {
+        loose: true,
+      },
+    ],
+    [
+      '@babel/plugin-proposal-object-rest-spread',
+      {
+        useBuiltIns: true,
+      },
+    ],
+    [
       '@babel/plugin-transform-runtime',
-    'transform-react-remove-prop-types',
+      {
+        corejs: false,
+        helpers: false, // Needed to support IE/Edge
+        regenerator: true,
+      },
+    ],
+    [
+      '@babel/plugin-transform-regenerator',
+      {
+        async: false,
+      },
+    ],
+    ['transform-react-remove-prop-types',
+      {
+        ignoreFilenames: ['node_modules'],
+        removeImport: true,
+      },
+    ],
     ['lodash', {
       id: [
         'lodash',

package.json

@@ -71,18 +71,23 @@
   "devDependencies": {
     "@babel/cli": "^7.5.0",
     "@babel/core": "^7.5.0",
-    "@babel/plugin-transform-runtime": "^7.5.0",
+    "@babel/plugin-proposal-class-properties": "^7.7.4",
+    "@babel/plugin-proposal-object-rest-spread": "^7.7.4",
+    "@babel/plugin-transform-regenerator": "^7.7.5",
+    "@babel/plugin-transform-runtime": "^7.7.6",
     "@babel/preset-env": "^7.5.0",
     "@babel/preset-react": "^7.0.0",
     "babel-eslint": "10.0.2",
     "babel-jest": "^24.8.0",
     "babel-loader": "^8.0.6",
     "babel-plugin-lodash": "^3.3.4",
+    "babel-plugin-macros": "^2.8.0",
     "babel-plugin-transform-react-remove-prop-types": "^0.4.24",
     "bundlewatch": "^0.2.5",
     "chalk": "^2.4.2",
     "codecov": "^3.5.0",
     "concurrently": "^4.1.1",
+    "core-js": "^3.4.8",
     "css-loader": "^3.0.0",
     "enzyme": "^3.10.0",
     "enzyme-adapter-react-16": "^1.14.0",
@@ -110,6 +115,8 @@
     "style-loader": "^0.23.1",
     "supertest": "^4.0.2",
     "terser-webpack-plugin": "^1.3.0",
+    "unfetch": "^4.1.0",
+    "url-polyfill": "^1.1.7",
     "webpack": "^4.35.3",
     "webpack-cli": "^3.3.5"
   },

src/polyfills.js

+/**
+ * Polyfill file used to build Webpack UMD build. These polyfills are needed to
+ * support both IE and Edge. If you are using Mirador ES imports these will not
+ * get bundled up.
+ */
+
+import 'core-js/stable'; // eslint-disable-line import/no-extraneous-dependencies
+import 'url-polyfill/url-polyfill'; // eslint-disable-line import/no-extraneous-dependencies
+import 'unfetch/polyfill'; // eslint-disable-line import/no-extraneous-dependencies

webpack.config.js

@@ -4,7 +4,7 @@ const TerserPlugin = require('terser-webpack-plugin');
 const paths = require('./config/paths');
 
 const babelLoaderConfig = {
-  include: paths.appSrc, // CRL
+  include: paths.appPath, // CRL
   loader: require.resolve('babel-loader'),
   options: {
     // Save disk space when time isn't as important
@@ -14,7 +14,6 @@ const babelLoaderConfig = {
   },
   test: /\.(js|mjs|jsx)$/,
 };
-
 const baseConfig = [
   {
     entry: './src/index-core.js',
@@ -31,7 +30,7 @@ const baseConfig = [
     },
   },
   {
-    entry: './src/index.js',
+    entry: ['./src/polyfills.js', './src/index.js'],
     module: {
       rules: [
         babelLoaderConfig,