const UglifyJsPlugin = require('uglifyjs-webpack-plugin'); module.exports = { optimization: { minimize: true, minimizer: [ new UglifyJsPlugin({ uglifyOptions: { warnings: false, parse: {}, compress: {}, mangle: true, // Note `mangle.properties` is `false` by default. output: null, toplevel: false, nameCache: null, ie8: false, keep_fnames: false, preserveComments: false }, }), ] }, externals: { jquery: 'jQuery' // Available and loaded through WordPress. }, mode: 'production', module: { rules: [{ test: /.js$/, exclude: /node_modules/, use: [{ loader: 'babel-loader', query: { presets: [ ['airbnb', { targets: { chrome: 50, ie: 11, firefox: 45 } }] ] } }] }] } };