JavaScript window.location does not set referer in the request header

Your post title shows that you want to change the current page programmatically using JavaScript but still having the HTTP referrer provided (from what I understood, using a <a> tag is just for a test case).

You need to be aware of cross-browser issues:

• The HTTP referrer header (HTTP-Referer) is set when changing window.location.href under the following browsers:
  • MSIE 9 (but probably any version above 9)
  • Firefox (at least 3.0, 3.5, 4.0, 5.0, but most probably all versions)
  • Chrome (at least 9, but most probably all versions)
  • Safari (at least 5, but most probably all versions)
  • Opera (at least 11, but most probably all versions)
• MSIE (at least 6, 7, 8): the referrer is not set when changing window.location.href (this is why some pseudo-solutions are based on myLink.click())
• Firefox (at least 3.0, 3.5, 4.0): the click function does not exist (this is why pseudo-solutions based on myLink.click() do not work)
• Firefox 5 : the click function exists under Firefox 5 but does not
  change the window location, so all the methods relying on the
  existence of the myLink.click() method will not work. Calling myLink.onclick() or myLink.onClick() raise an error (“onclick is not a function”), so solutions based on these calls will not work.

In order to manage these cross-browser issues, I’m using the following method:

function navigateToUrl(url) {
    var f = document.createElement("FORM");
    f.action = url;

    var indexQM = url.indexOf("?");
    if (indexQM>=0) {
        // the URL has parameters => convert them to hidden form inputs
        var params = url.substring(indexQM+1).split("&");
        for (var i=0; i<params.length; i++) {
            var keyValuePair = params[i].split("=");
            var input = document.createElement("INPUT");
            input.type="hidden";
            input.name  = keyValuePair[0];
            input.value = keyValuePair[1];
            f.appendChild(input);
        }
    }

    document.body.appendChild(f);
    f.submit();
}

navigateToUrl("http://foo.com/bar");

This solution works on all the browser flavors and version listed above. It has the advantage to be simple, multi-browser and easy to understand.
Note that this has not been tested under HTTPS.