Created by: martinfrancois
As pointed out here: https://github.com/facebook/create-react-app/issues/9913#issuecomment-716879695
The comment in the code clearly states // which is why it's disabled by default.
suggesting react-refresh
should be disabled by default.
But if the environment variable FAST_REFRESH
is not set at all, the condition process.env.FAST_REFRESH !== 'false'
evaluates to true
(as undefined !== 'false'
), enabling react-refresh
.