title: Is it possible to stop browsers from caching favicon.ico?
body: <p>I have <code>/favicon.ico</code> aliased to a PHP script that randomly chooses one of several icons every time it is accessed, by returning a <code>Location</code> header to the location of the chosen icon.</p>
  
  <p>However, I want a (potentially) different icon to be shown each time, though Chrome (only browser I've tested) appears to cache the icon for quite some time. I have added these headers to both the <code>favicon.ico</code> redirection and the PNG icon files themselves, however, the icon still gets cached by the browser.</p>
  
  <pre><code>Cache-Control: no-cache, no-store, must-revalidate
  Pragma: no-cache
  Expires: 0
  </code></pre>
  
  <p>I am using nginx. Is there any way to force the browser to refresh the icon every visit? Using the <code>&lt;link&gt;</code> tag in HTML is not an option for me.</p>