If you're upgrading from Version 4, there are a number of changes that you need to be aware of before you jump into Version 6. We've tried to make it as painless as possible, but you may need to make some changes in your project to have it work correctly.
I’m getting a Babel/Babel-loader error when using React Font Awesome
If you’re using a Mac or Linux, make sure you are up to date on the latest versions by running brew update and brew upgrade. Or delete your package.json.lock file and Node_Modules folder and then run either npm install or yarn install to reinstall all packages and dependencies.