Webpack / Babel / React build error: "Unknown option: foo/node_modules/react/react.js.Children"
I just wanted to add that I got the error after I uninstalled an old npm module I wasn't using in my project anymore. Which was weird because I wasn't using it anywhere - how could uninstalling something that isn't used anywhere cause an error?
Turns out that one of that modules sub-dependencies had babel-preset-react, which I had missed installing to my own project when I started it. Thus, uninstalling that package also uninstalled the critical babel-preset-react!
For over a year, my react app could compile thanks to another package's sub-dependency...
So yes, installing babel-preset-react solved the issue for me.