Force Cache-Control: no-cache in Chrome via XMLHttpRequest on F5 reload

Using a query string for cache control isn't your best option nowadays for multiple reasons, and (only) a few are mentioned in this answer. He even explains the new standard method of version control. Though if you just want to be able to set your request headers, the right way to do it is:

    // via Cache-Control header:
    xhr.setRequestHeader("Cache-Control", "no-cache, no-store, max-age=0");
    
    // fallbacks for IE and older browsers:
    xhr.setRequestHeader("Expires", "Tue, 01 Jan 1980 1:00:00 GMT");
    xhr.setRequestHeader("Pragma", "no-cache"); //Edit: I noticed this is required for Chrome some time ago... forgot to mention here

Hope this helps anyone in the future.

An alternative would be to append a unique number to the url.

<script>
    var xhr = new XMLHttpRequest;
    xhr.open('GET', 'test.html?_=' + new Date().getTime());
    //xhr.setRequestHeader('Cache-Control', 'no-cache');
    xhr.send();
</script>

timestamp isn't quite unique, but it should be unique enough for your usecase.