Setting a cookie for a different domain in JavaScript can be a bit tricky due to security restrictions. But, you can use the document.domain property to set cookie for a subdomain or a parent domain.
Here is an example:
document.domain = "(link unavailable)";
setCookie("myCookie", "value", 30);
This sets the cookie "myCookie" with value "value" for the domain "(link unavailable)" and its subdomains.
Alternatively, you can use the domain parameter when setting the cookie:
setCookie("myCookie", "value", 30, {domain: ".(link unavailable)"});
That sets the cookie "myCookie" with value "value" for the domain "(link unavailable)" and its subdomains.