https://www.maria-black.com/site-selector/assets/js/main.js

1window.onload = function () {
2    const links = document.querySelectorAll('.country');
3    const checkbox = document.querySelector('#checkbox');
4
5    setLinkCookies(links, checkbox.checked); // true by default from checkbox.
6
7    checkbox.addEventListener('click', e => {
8        setLinkCookies(links, checkbox.checked);
9    });
10
11    for (let i = 0; i < links.length; i++) {
12        links[i].addEventListener('click', ev => {
13            ev.preventDefault();
14            ev.stopPropagation();
15            location.href = addQueryToHref(links[i].href);
16            return false;
17        });
18    }
19};