How to edit a react package locally - reactjs

Question

I want to edit the react-js-cron package (switching antd with bootstrap). I followed this tutorial and the link worked. I can see the symbolic link in the IDE and if I do changes in the local react-js-cron package it is being reflected in the other. But when I load the test app (without any changes) in the react-js-cron package and just the symbolic link it throws an error:
Uncaught TypeError: Cannot read properties of null (reading 'useRef')
at useRef (react.development.js:1630:1)
at Cron (Cron.js:45:1)
at renderWithHooks (react-dom.development.js:12740:1)
at mountIndeterminateComponent (react-dom.development.js:14670:1)
at beginWork (react-dom.development.js:15194:1)
at performUnitOfWork (react-dom.development.js:18780:1)
at workLoop (react-dom.development.js:18820:1)
at HTMLUnknownElement.callCallback (react-dom.development.js:149:1)
at Object.invokeGuardedCallbackDev (react-dom.development.js:199:1)
at invokeGuardedCallback (react-dom.development.js:256:1)
useRef # react.development.js:1630
Cron # Cron.js:45
renderWithHooks # react-dom.development.js:12740
mountIndeterminateComponent # react-dom.development.js:14670
beginWork # react-dom.development.js:15194
performUnitOfWork # react-dom.development.js:18780
workLoop # react-dom.development.js:18820
callCallback # react-dom.development.js:149
invokeGuardedCallbackDev # react-dom.development.js:199
invokeGuardedCallback # react-dom.development.js:256
replayUnitOfWork # react-dom.development.js:18052
renderRoot # react-dom.development.js:18936
performWorkOnRoot # react-dom.development.js:19800
performWork # react-dom.development.js:19712
performSyncWork # react-dom.development.js:19686
requestWork # react-dom.development.js:19555
scheduleWork # react-dom.development.js:19364
scheduleRootUpdate # react-dom.development.js:20032
updateContainerAtExpirationTime # react-dom.development.js:20060
updateContainer # react-dom.development.js:20117
ReactRoot.render # react-dom.development.js:20413
(anonymous) # react-dom.development.js:20550
unbatchedUpdates # react-dom.development.js:19915
legacyRenderSubtreeIntoContainer # react-dom.development.js:20546
render # react-dom.development.js:20615
./src/index.js # index.js:14
options.factory # react refresh:6
__webpack_require__ # bootstrap:24
(anonymous) # startup:7
(anonymous) # startup:7
react-dom.development.js:16638 The above error occurred in the <Cron> component:
in Cron (at App.js:26)
in header (at App.js:13)
in div (at App.js:12)
in App (at src/index.js:15)
I didn't do any changes, how can this throw an error? I did downgrade my app's react version to 16.8, the min dependency in react-js-cron but didn't help.
To clarify:
I created an app with create react app: npx create-react-app my-test-proj-cron && npm i --save react-js-cron; worked, I can use the package in the UI
git clone https://github.com/xrutayisire/react-js-cron.git; then inside that folder I did npm i && npm build && yarn link
Then I went into the my-test-proj-cron folder and linked it with yarn link "react-js-cron"
After this, I'm getting the error. Shouldn't my-test-proj-cron/node_modules/react-js-cron and the locally checked out react-js-cron be the same? why does it throw an error then?