Polyfill for array.prototype.includes according to the ECMAScript 2019 specification. The code itself is licensed under Public Domain and taken from https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/includes#Polyfill.
Even though this package has es7 in its name, it is regularly updated to the current polyfill source code presented at MDN. The current version there is based on ECMAScript 2019.
Install using npm install es7-array.prototype.includes and activate the polyfill
by writing require('es7-array.prototype.includes') somewhere in your application.