1. yarn add react-app-polyfill
2. src/index.js 文件开始处增加如下代码
import 'react-app-polyfill/ie9'; // ie9 include ie11
import 'react-app-polyfill/stable';
3. 删除node_modules目录后yarn
4. public/index.html 文件 <head>标签内增加如下代码
<meta http-equiv="X-UA-Compatible" content="IE=edge" />