react__WEBPACK_IMPORTED_MODULE_1___default.a.createPortal is not a function code example
Example: __WEBPACK_IMPORTED_MODULE_0_react___default.a.createContext is not a function
react-redux v6.0.0 uses the new context api provided by React
and in order for it work, either you need to downgrade react-redux to v5.x.x
or upgrade react and react-dom to v16.4 or above
npm update react react-dom