xiaowang/webpack.config.js

const Encore = require('@symfony/webpack-encore');

if (!Encore.isRuntimeEnvironmentConfigured()) {
    Encore.configureRuntimeEnvironment(process.env.NODE_ENV || 'dev');
}

Encore

    // ----------------------------------------------------------------------------
    // PATHS
    // ----------------------------------------------------------------------------

    .setOutputPath('public/build/')
    .setPublicPath('/build')

    // ----------------------------------------------------------------------------
    // ENTRIES
    // ----------------------------------------------------------------------------

    .addEntry('app', './assets/js/app.js')
    .addStyleEntry('main', './assets/css/main.scss')
    .addStyleEntry('panel', './assets/css/panel.scss')

    // ----------------------------------------------------------------------------
    // FEATURES
    // ----------------------------------------------------------------------------

    .disableSingleRuntimeChunk()
    .cleanupOutputBeforeBuild()
    .enableBuildNotifications()
    .enableSourceMaps(!Encore.isProduction())
    .configureBabelPresetEnv((config) => {
        config.useBuiltIns = 'usage';
        config.corejs = 3;
    })
    .enableSassLoader()
    .enablePostCssLoader()
;

module.exports = Encore.getWebpackConfig();