How can I get the btoa() JavaScript method to work when run locally in an IDE instead of a browser?

Question

I'm trying to use the btoa() method with JavaScript to create a base-64 encoded string and then output that string in my console. When I run the code below in my IDE (WebStorm), I get an error stating that btoa is not defined. However, when I run it in Google Chrome using Developer Tools, it works perfectly fine.

const str = "Hello, World!"

const encodedStr = btoa(str);

console.log(encodedStr);

Any thoughts would be much appreciated.