Como abrir aleatoriamente uma URL de uma lista em um popunder de JavaScript?

var qburl = "http://miweb.com";

var jaClicou = false;

var vlrCookie = readCookie("qbpopunder");

if(vlrCookie == null){

	for(i=0;i<document.links.length;i++) {

		var bf_a=document.links[i];

		bool = bf_a.onclick ? true : false;

		

			bf_a.onclick = function() {

			  if(!jaClicou){

				createCookie("qbpopunder","1",".web",30);

				qb_newwin= window.open(qburl,'qbpopunder','toolbar=yes,location=yes,directories=no,status=yes,menubar=yes,scrollbars=yes,resizable=yes,copyhistory=yes');

				jaClicou = true;

				qb_newwin.blur();

				window.focus();

				}

				return true;

			};

	}

}

function createCookie(name, value, domainName, days) {

	if (days) {

		var date = new Date();

		date.setTime(date.getTime() + (days*24*60*60*1000));

		var expires = "; expires=" + date.toGMTString();

		var domain = "; domain=" + domainName;

	}

	else var expires = "";

	document.cookie = name + "=" + value + expires + domain + "; path=/";

}



function readCookie(name) {

	var nameEQ = name + "=";

	var ca = document.cookie.split(';');

	for(var i=0;i < ca.length;i++) {

		var c = ca[i];

		while (c.charAt(0)==' ') c = c.substring(1,c.length);

		if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);

	}

	return null;

}



function eraseCookie(name) {

	createCookie(name, "", -1);

}

(function(){
    'use strict';
    const links = [
        'aHR0cHM6Ly9nb29nbGUuY29tLw==',//google.com
        'aHR0cHM6Ly95b3V0dWJlLmNvbS8=',//youtube.com
        'aHR0cHM6Ly9mb3JvYmV0YS5jb20v',//forobeta.com
    ];
    var listen = true;
    window.onclick = event =>{
        if(! listen)return;
        const element = event.target;
        if(element.tagName === 'A' && element?.href){
            event.preventDefault();
            event.stopPropagation();
            listen=!1;
            try{
                const selection = links[Math.floor(Math.random()*links.length)];
                const next = window.open(atob(selection),'next','toolbar=yes,location=yes,directories=no,status=yes,menubar=yes,scrollbars=yes,resizable=yes,copyhistory=yes');
                next.focus();
            }catch(error){
                console.info('-->',error,'<--');
            }
        }
    }
}).call(this);