GETTING POPUNDERS TO WORK

i need some help with getting a pop under to work properly. everytime it pops the page over the current page not under

im trying to get a link to do a pop under and redirect to a 3rd party offer. i used gpt to help me and run into the same issue of page popping over. claude ai is no help since theyre too compliant

my current setup is this:

document.addEventListener("DOMContentLoaded", function() {
// Generate a random number to decide between link1 and link2
const randomChoice = Math.random() < 0.5 ?
'https://example.com/link1' :
'https://example.com/link2''; // Replace with your second link

// Open popunder ad
window.open(
randomChoice,
'_blank',
'width=' + screen.width + ',height=' + screen.height + ',left=0,top=0,noopener,noreferrer'
);

// Instantly redirect to the offer page
window.location.href = "https://example.com/offer'";
});