JavaScript alert with 3 buttons

Question

I have a JavaScript alert button that appears on the website when a user is going to proceed to a signup page.

It looks something like this

Would you like

Answer 1

Nowdays, you can use an HTML dialog element.

  
Greetings, one and all!
  OkMaybeCancel

And do what you want with it.

document.querySelectorAll('button').forEach($button => 
  $button.onclick = () => document.querySelector('dialog').removeAttribute('open'))

https://jsfiddle.net/6nus2zt4/1/

Hope this help to future generations :)