What the difference between MongoDB Realm JS and standard JS?

Hi, I’m working with MongoDB Realm Functions and found unexpected behavior while I was trying to check for network response status code.

const response = await context.http.get({ url: 'https://api.github.com/asd' });
console.log(response.statusCode); // 404
console.log(typeof 404); // number
console.log(typeof response.statusCode); // number
console.log(response.statusCode == 404); // true
console.log(response.statusCode === 404); // true
console.log([404].includes(404)); // true
console.log([404].includes(response.statusCode.valueOf())); // true
console.log([404].includes(response.statusCode)); // false

So I’m curious why both == and === evaluates to true while includes evaluates to false for a statusCode field which is number? Where I can read about the difference between MongoDB Realm JS and standard JS to improve my expectations? Thanks!