Заменил пресет es-2015 на env и добавил плагины для обработки свойств класса

cp/.babelrc

 {
+  "plugins": [
+    "transform-class-properties",
+    ["transform-runtime", {
+      "polyfill": false,
+      "regenerator": true
+    }]
+  ],
+
   "presets": [
-    "es2015", "stage-0", "react"
+    "env", "react"
   ]
 }
\ No newline at end of file

cp/package.json

@@ -14,14 +14,16 @@
     "react": "^16.3.2",
     "react-dom": "^16.3.0",
     "react-icons": "^2.2.7",
-    "reactstrap": "^5.0.0-beta.3"
+    "reactstrap": "^5.0.0-beta.3",
+    "whatwg-fetch": "^2.0.4"
   },
   "devDependencies": {
     "babel-core": "^6.26.0",
     "babel-loader": "^7.1.4",
-    "babel-preset-es2015": "^6.24.1",
+    "babel-plugin-transform-class-properties": "^6.24.1",
+    "babel-plugin-transform-runtime": "^6.23.0",
+    "babel-preset-env": "^1.7.0",
     "babel-preset-react": "^6.24.1",
-    "babel-preset-stage-0": "^6.24.1",
     "css-loader": "^0.28.11",
     "style-loader": "^0.20.3",
     "webpack": "^4.4.1",

cp/webpack.config.js

@@ -4,7 +4,7 @@ const webpack = require("webpack");
 module.exports = {
     entry: [
         // Application code
-        "./javascript/src/typos.jsx",
+        "./javascript/src/typos.jsx"
     ],
 
     output: {