Support IE 11.

https://medium.com/@ramez.aijaz/transpile-typescript-to-es5-using-babel-and-webpack-f3b72a157399

babel.config.js

@@ -0,0 +1,29 @@
+module.exports = function(api) {
+  api.cache(false);
+  const presets = [
+    [
+      "@babel/preset-env",
+      {
+        "corejs": { "version": 3 },
+        "useBuiltIns": "usage",
+        "targets": {
+          "edge": "17",
+          "firefox": "60",
+          "chrome": "67",
+          "safari": "11.1",
+          "ie": "11"
+        }
+      }
+    ]
+  ];
+  const plugins = [
+    ["@babel/plugin-proposal-decorators", { "decoratorsBeforeExport": true }],
+    ["@babel/plugin-proposal-class-properties"],
+    ["@babel/transform-runtime"]
+  ];
+
+  return {
+    presets,
+    plugins
+  };
+};

package.json

@@ -8,6 +8,8 @@
   },
   "dependencies": {
     "@babel/core": "^7.16.10",
+    "@babel/plugin-proposal-class-properties": "^7.16.7",
+    "@babel/plugin-proposal-decorators": "^7.17.2",
     "@babel/plugin-transform-runtime": "^7.16.10",
     "@babel/preset-env": "^7.16.10",
     "@babel/runtime": "^7.16.7",
@@ -47,11 +49,6 @@
   "resolutions": {
     "chokidar": "^3.5.2"
   },
-  "babel": {
-    "presets": [
-      "./node_modules/shakapacker/package/babel/preset.js"
-    ]
-  },
   "browserslist": [
     "defaults"
   ],

yarn.lock

@@ -76,7 +76,7 @@
     browserslist "^4.17.5"
     semver "^6.3.0"
 
-"@babel/helper-create-class-features-plugin@^7.16.10", "@babel/helper-create-class-features-plugin@^7.16.7", "@babel/helper-create-class-features-plugin@^7.17.6":
+"@babel/helper-create-class-features-plugin@^7.16.10", "@babel/helper-create-class-features-plugin@^7.16.7", "@babel/helper-create-class-features-plugin@^7.17.1", "@babel/helper-create-class-features-plugin@^7.17.6":
   version "7.17.6"
   resolved "https://registry.npmmirror.com/@babel/helper-create-class-features-plugin/-/helper-create-class-features-plugin-7.17.6.tgz#3778c1ed09a7f3e65e6d6e0f6fbfcc53809d92c9"
   integrity sha512-SogLLSxXm2OkBbSsHZMM4tUi8fUzjs63AT/d0YQIzr6GSd8Hxsbk2KYDX0k0DweAzGMj/YWeiCsorIdtdcW8Eg==
@@ -314,6 +314,17 @@
     "@babel/helper-plugin-utils" "^7.16.7"
     "@babel/plugin-syntax-class-static-block" "^7.14.5"
 
+"@babel/plugin-proposal-decorators@^7.17.2":
+  version "7.17.2"
+  resolved "https://registry.npmmirror.com/@babel/plugin-proposal-decorators/-/plugin-proposal-decorators-7.17.2.tgz#c36372ddfe0360cac1ee331a238310bddca11493"
+  integrity sha512-WH8Z95CwTq/W8rFbMqb9p3hicpt4RX4f0K659ax2VHxgOyT6qQmUaEVEjIh4WR9Eh9NymkVn5vwsrE68fAQNUw==
+  dependencies:
+    "@babel/helper-create-class-features-plugin" "^7.17.1"
+    "@babel/helper-plugin-utils" "^7.16.7"
+    "@babel/helper-replace-supers" "^7.16.7"
+    "@babel/plugin-syntax-decorators" "^7.17.0"
+    charcodes "^0.2.0"
+
 "@babel/plugin-proposal-dynamic-import@^7.16.7":
   version "7.16.7"
   resolved "https://registry.npmmirror.com/@babel/plugin-proposal-dynamic-import/-/plugin-proposal-dynamic-import-7.16.7.tgz#c19c897eaa46b27634a00fee9fb7d829158704b2"
@@ -437,6 +448,13 @@
   dependencies:
     "@babel/helper-plugin-utils" "^7.14.5"
 
+"@babel/plugin-syntax-decorators@^7.17.0":
+  version "7.17.0"
+  resolved "https://registry.npmmirror.com/@babel/plugin-syntax-decorators/-/plugin-syntax-decorators-7.17.0.tgz#a2be3b2c9fe7d78bd4994e790896bc411e2f166d"
+  integrity sha512-qWe85yCXsvDEluNP0OyeQjH63DlhAR3W7K9BxxU1MvbDb48tgBG+Ao6IJJ6smPDrrVzSQZrbF6donpkFBMcs3A==
+  dependencies:
+    "@babel/helper-plugin-utils" "^7.16.7"
+
 "@babel/plugin-syntax-dynamic-import@^7.8.3":
   version "7.8.3"
   resolved "https://registry.npmmirror.com/@babel/plugin-syntax-dynamic-import/-/plugin-syntax-dynamic-import-7.8.3.tgz#62bf98b2da3cd21d626154fc96ee5b3cb68eacb3"
@@ -1625,6 +1643,11 @@ chalk@^4.0:
     ansi-styles "^4.1.0"
     supports-color "^7.1.0"
 
+charcodes@^0.2.0:
+  version "0.2.0"
+  resolved "https://registry.npmmirror.com/charcodes/-/charcodes-0.2.0.tgz#5208d327e6cc05f99eb80ffc814707572d1f14e4"
+  integrity sha512-Y4kiDb+AM4Ecy58YkuZrrSRJBDQdQ2L+NyS1vHHFtNtUjgutcZfx3yp1dAONI/oPaPmyGfCLx5CxL+zauIMyKQ==
+
 "chokidar@>=3.0.0 <4.0.0", chokidar@^3.5.2, chokidar@^3.5.3:
   version "3.5.3"
   resolved "https://registry.npmmirror.com/chokidar/-/chokidar-3.5.3.tgz#1cf37c8707b932bd1af1ae22c0432e2acd1903bd"