Sending XMLHttpRequest with Referer header changed?

Question

JavaScript

I need to send a request (XMLHttpRequest) from site.ru to site.ru/req with the header Referer: 'site.ru/ref'. I tried the setRequestHeader('Referer', 'site.ru/ref') method of the XMLHttpRequest object, but for security reasons, some headers cannot be changed (Google Chrome browser).
Then the idea came to create an iframe, load site.ru/ref into it, and send a request from this iframe, in theory, in this way, the value of the iframe address will be put in the Referer header.
Tell me how to send a request from an iframe, or if this does not work, an alternative method of replacing the Referer header.

Answer 1

Any iframe has a contentWindow property, through which we can accordingly get the xhr of the page. Well, for example:

// ifr - наш ифрейм
var xhr = new ifr.contentWindow.XMLHTTPRequest();

As an example - http://uadminjs.ucoz.ru/blog/2011-10-15-5 .
(this is a JS framework for CMS uCoz)