Looks like @ionic/app-scripts isn't installed in this project.

百度之后参考以下链接 https://blog.csdn.net/liweibo348/article/details/83625221 本地删除node_modules文件夹，然后npm install 报错：Failed at the [email protected] postinstall script.   不管它，继续ionic serve，报错  之后执行：npm install @

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