Webpack - extract-text-webpack-plugin Cannot find module
Do you have webpack module on your project?
If not, install it locally (not globally):
$ npm install webpack [--save-dev]extract-text-webpack-plugin needs webpack as peer dependency, but npm 3 doesn't install peer dependencies automatically.
You can try this command which I found on https://www.npmjs.com/package/extract-text-webpack-plugin
npm i extract-text-webpack-plugin
I solve it by use
npm install extract-text-webpack-plugin --save-dev