webpack.config.js

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

Encore
    .copyFiles([
        {from: './node_modules/ckeditor/', to: 'ckeditor/[path][name].[ext]', pattern: /\.(js|css)$/, includeSubdirectories: false},
        {from: './node_modules/ckeditor/adapters', to: 'ckeditor/adapters/[path][name].[ext]'},
        {from: './node_modules/ckeditor/lang', to: 'ckeditor/lang/[path][name].[ext]'},
        {from: './node_modules/ckeditor/plugins', to: 'ckeditor/plugins/[path][name].[ext]'},
        {from: './node_modules/ckeditor/skins', to: 'ckeditor/skins/[path][name].[ext]'}
    ])
    // directory where compiled assets will be stored
    .setOutputPath('public/build/')
    // public path used by the web server to access the output path
    .setPublicPath('/build')
    // only needed for CDN's or sub-directory deploy
    //.setManifestKeyPrefix('build/')

    /*
     * ENTRY CONFIG
     *
     * Add 1 entry for each "page" of your app
     * (including one that's included on every page - e.g. "app")
     *
     * Each entry will result in one JavaScript file (e.g. app.js)
     * and one CSS file (e.g. app.css) if you JavaScript imports CSS.
     */
    .addEntry('app', './assets/js/app.js')
    .addEntry('admin', './assets/js/admin.js')
    //.addEntry('page1', './assets/js/page1.js')
    //.addEntry('page2', './assets/js/page2.js')

    // will require an extra script tag for runtime.js
    // but, you probably want this, unless you're building a single-page app
    .enableSingleRuntimeChunk()

    /*
     * FEATURE CONFIG
     *
     * Enable & configure other features below. For a full
     * list of features, see:
     * https://symfony.com/doc/current/frontend.html#adding-more-features
     */
    .addPlugin(new webpack.ProvidePlugin({
        $: 'jquery',
        jQuery: 'jquery',
        'window.jQuery': 'jquery',
        Popper: ['popper.js', 'default']
    }))
    .cleanupOutputBeforeBuild()
    .enableBuildNotifications()
    .enableSourceMaps(!Encore.isProduction())
    // enables hashed filenames (e.g. app.abc123.css)
    .enableVersioning(Encore.isProduction())

    // enables Sass/SCSS support
    .enableSassLoader()

    // uncomment if you use TypeScript
    //.enableTypeScriptLoader()

    // uncomment if you're having problems with a jQuery plugin
    .autoProvidejQuery()
;

module.exports = Encore.getWebpackConfig();