Using React 17 in the angular 11 gives the error React is not defined when makes prod build but working fine in dev build.

Hi I am following this URL to integrate React in angular https://medium.com/@zacky_14189/embedding-react-components-in-angular-the-easy-way-60f796b68aef

But when I make production build then in the browser console I got the error
main.597a58e09c20f4baf37b.js:1 ERROR ReferenceError: React is not defined
at e.render (14.30350cdd70a75b908595.js:1)
at e.ngAfterViewInit (14.30350cdd70a75b908595.js:1)
at Jt (main.597a58e09c20f4baf37b.js:1)
at $t (main.597a58e09c20f4baf37b.js:1)
at Zt (main.597a58e09c20f4baf37b.js:1)
at on (main.597a58e09c20f4baf37b.js:1)
at main.597a58e09c20f4baf37b.js:1
at on (main.597a58e09c20f4baf37b.js:1)
at Rn (main.597a58e09c20f4baf37b.js:1)
at main.597a58e09c20f4baf37b.js:1