Build error for WeakRef Class

[jamesgjt]

Hi,

I use create-react-app to create the app for me, and I have create some js file that use the WeakRef class in my react app.
When I run npm start command, it is running fine and able to compile.
However, when I run npm run build for the project. the eslint compiler failed to compile with error message WeakRef is not defined

Anyone encounter this behavior?