Do you know prior to the Tokyo Release, ServiceNow’s server-side JavaScript utilized ECMAScript 5. “ECMAScript” is basically the version of JavaScript. Newer versions have come out with some helpful functionality.

The client-side script runs in your web browser so usually, any client script you’ve made on ServiceNow could utilize the newest JavaScript features, but any script running on the server was limited to ES5.

To utilize ECMAScript 2021 on your app, just follow these simple steps:

1. Make sure your instance is upgraded to Tokyo.
2. Create a new app via your preferred method (eg. Studio or App Engine Studio)
3. Open the sys_app page for your app.

4. Under “Design and Runtime” change “JavaScript Mode” to ECMAScript2021(ES12).

5. Save your record. That’s it.