const { environment } = require('@rails/webpacker') module.exports = environment function hotfixPostcssLoaderConfig (subloader) { const subloaderName = subloader.loader if (subloaderName === 'postcss-loader') { if (subloader.options.postcssOptions) { console.log( '\x1b[31m%s\x1b[0m', 'Remove postcssOptions workaround in config/webpack/environment.js' ) } else { subloader.options.postcssOptions = subloader.options.config; delete subloader.options.config; } } } environment.loaders.keys().forEach(loaderName => { const loader = environment.loaders.get(loaderName); loader.use.forEach(hotfixPostcssLoaderConfig); });