在用npm安装插件时，出现了一条警告：
npm WARN deprecated core-js@2.6.12: core-js@<3.3 is no longer maintained and not recommended for usage due to the number of issues. Because of the V8 engine whims, feature de tection in old core-js versions could cause a slowdown up to 100x even if nothing is polyfilled. Please, upgrade your dependencies to the actual version of core-js.
解决方法:
npm install -g core-js@3.1.1
也可以npm i core-js
然后
npm i chokidar
