instadiff.js

const usernameClassname = 'zsYNt';
const modal = document.getElementsByClassName('j6cq2')[0]
const followingButton = document.getElementsByClassName('-nal3')[0]

let x = 0;
let followingOn = false;

setInterval(() => {
  modal.scrollTo(0, modal.scrollHeight);
}, 2000);

const followings = Array.from(document.getElementsByClassName(usernameClassname)).map(el => el.innerHTML);
const followers = Array.from(document.getElementsByClassName(usernameClassname)).map(el => el.innerHTML);

console.log(followings.filter(x => !followers.includes(x)));