Blockstack-react-scripts fails

I build a react app with create-react-app and then copied the required changes from blockstack-react-scripts to make it work nicely. CORS is solved.

However, I get an error when building a production version:

Failed to minify the code from this file:

I see in blockstack-react-script that tiny-secp256k1/ecurve.js is handled but not rfc6979. Is this a problem with my code/package.json? Or with blockstack-react-scripts? (Unfortuntately, there is no possibility to create an issue on github for that)

Not sure whether the PR is correct : is probably the best one to answer questions about this!