how to transpile newer Javascript code for ECMAScript 5.1

[mr-c]

One recipe is to use
https://babeljs.io/

$ npm install -G @babel/core @babel/cli @babel/preset-env
$ babel --presets  @babel/preset-env some_javascript.js > some_javascript_es5.1.js

or

$ sudo apt install babeljs
$ babeljs --presets /usr/share/nodejs/@babel/preset-env/ underscore-esm-min.js some_javascript.js > some_javascript_es5.1.js

You may need to insert var exports = new Object(); after the "use strict"; at the top of the output.