Map is undefined in ie9

[kwzm]

• Operating System: win7 64bit
• Node Version: 8.12.0
• NPM Version: 6.4.1
• webpack Version: 4.9.1
• webpack-dev-server Version: 3.1.9

• This is a bug
• This is a modification request

Code

use create-react-app

Expected Behavior

webpack-dev-server can run in ie9

Actual Behavior

I use create-react-app init a application, and view the page in ie9 in dev environment, but found this error:

in English is Map is undefined

I know webpack-dev-server from 2.8.0 use es6 syntax, so I want use babel to translate it:

1. I use babel-loader to compile it:

2. I try to use @babel/polyfill
   import '@babel/polyfill'

3. I try to use core-js
   import 'core-js/es/array/map'

But never work, the error is still there.

For Bugs; How can we reproduce the behavior?

use create-react-app init a app and npm start then open ie9 view the page

For Features; What is the motivation and/or use-case for the feature?

[montogeek]

Try with https://github.com/zloirock/core-js#map not Array.prototype.map

[alexander-akait]

Please post this issue in create-react-app

[kwzm]

@montogeek Thanks I will try.

[kwzm]

@montogeek I tried it, but didn't work, I guess maybe is create-react-app's bug as @evilebottnawi said.