Flow Enums correctly parsed but not transformed - babeljs

Question

In my React app, I'm trying to migrate from my "old school" JS enums to Flow Enums:
https://flow.org/en/docs/enums/
(I think) I've done everything listed here:
https://flow.org/en/docs/enums/enabling-enums/
eslint and flow check are both happy (zero error) and the enums work as expected when I type code.
But when I start my app, they are not transformed and I get this:
ERROR in ./src/types.js
Module build failed (from ../../node_modules/babel-loader/lib/index.js):
SyntaxError: C:\foo\src\types.js: Unexpected token, expected "{" (16:7)
14 | |};
15 |
> 16 | export enum FooEnum {
| ^
17 | On,
18 | Off,
19 | Default
at instantiate (C:\foo\node_modules\#babel\parser\lib\index.js:72:32)
at constructor (C:\foo\node_modules\#babel\parser\lib\index.js:366:12)
at FlowParserMixin.raise (C:\foo\node_modules\#babel\parser\lib\index.js:3453:19)
at FlowParserMixin.unexpected (C:\foo\node_modules\#babel\parser\lib\index.js:3491:16)
at FlowParserMixin.parseExport (C:\foo\node_modules\#babel\parser\lib\index.js:16044:16)
at FlowParserMixin.parseExport (C:\foo\node_modules\#babel\parser\lib\index.js:6170:24)
at FlowParserMixin.parseStatementContent (C:\foo\node_modules\#babel\parser\lib\index.js:14893:27)
at FlowParserMixin.parseStatement (C:\foo\node_modules\#babel\parser\lib\index.js:14777:17)
at FlowParserMixin.parseStatement (C:\foo\node_modules\#babel\parser\lib\index.js:5951:24)
at FlowParserMixin.parseBlockOrModuleBlockBody (C:\foo\node_modules\#babel\parser\lib\index.js:15420:25)
Package-wise, all of them are in their latest version and I've installed:
babel-plugin-transform-flow-enums
eslint-plugin-ft-flow
flow-enums-runtime
My Babel config is:
"babel": {
"plugins": [
"#babel/plugin-proposal-class-properties",
[
"#babel/plugin-syntax-flow",
{
"enums": true
}
],
"babel-plugin-transform-flow-enums"
],
"presets": [
"#babel/preset-env",
"#babel/preset-flow",
"#babel/preset-react"
]
},
Also, calling Babel from a command line correctly transforms the enum. I'm using this command:
npx babel src/types.js
What could I have missed?

Answer 1

So, after struggling for hours, I eventually found out that
react-app-rewired was messing up with my Babel plugins.
I ended up installing customize-cra, which allowed me to explicitely use my Babel config:
const {useBabelRc, override} = require('customize-cra');
module.exports = override(
useBabelRc()
);