The latest version is not compatible with ie 9?

[An0nymous0]

Version

3.0.0-beta.6

Reproduction link

https://github.com/vuejs/vue-cli/releases/tag/v3.0.0-beta.6

Steps to reproduce

1.vue.config.js

module.exports = {
configureWebpack: {
entry: [
'babel-polyfill',
'./src/main.js'
]
}
}

2.main.js

import 'babel-polyfill'

3.npm run serve

SCRIPT1002:语法错误

What is expected?

IE9-IE11正常访问

What is actually happening?

IE9 无法正常访问

[posva]

Duplicate of #858