In order to solve the issue with using

supertokens-react-theme

locally inside another repo such as

supertokens-demo-react

, you will have to remove conflicting modules when running locally. Note that this issue is only happening in local environment. That's why it's recommended to simply run

npm run start

when you want to modify a theme, and then from your project, reference the remote package (on github or npm) after you have made your changes. Does that make sense?