I've recently been playing with koa.js - which happens to lean on ES6 features quite heavily. Also using this as an opportunity to learn to use VS Code. Loving both tools incidentally.

Code supports ES6 nicely, however you do need to configure your working directory to tell the IDE that you want to use it. Just add a jsconfig.json file to your directory root and add the following:

  "compilerOptions": {
    "target": "ES6"

While you are there you may want to setup other features!