What are the approaches to include polyfills in your create-react-app?

In Create React App, you can include polyfills to support older browsers by using the "core-js" library, the "@babel/preset-env" package, or the "react-app-polyfill" package. These packages provide polyfills for various ES6+ features and browser APIs, and can be configured in the "babel.config.js" or "webpack.config.js" files.