new: dev: upgrade to the latest symfony v4 #3

assets/js/app.js

@@ -0,0 +1,14 @@
+/*
+ * Welcome to your app's main JavaScript file!
+ *
+ * We recommend including the built version of this JavaScript file
+ * (and its CSS file) in your base layout (base.html.twig).
+ */
+
+// any CSS you require will output into a single css file (app.css in this case)
+require('../css/app.css');
+
+// Need jQuery? Install it with "yarn add jquery", then uncomment to require it.
+// const $ = require('jquery');
+
+console.log('Hello Webpack Encore! Edit me in assets/js/app.js');