title: Iframe src caching issue on firefox
body: <p>I have an iframe element with a random scr attribute. When I do refresh the page every time, the iframe should load the page with different query parameters based on the src attribute. But in firefox, if I try to load dynamic URL in an iframe, it always execute the first time executed URL eventhough the src attribute changes dynamically. The query parameters also not passing correctly. So, how I can solve this issue?</p>
  
  <p>eg:</p>
  
  <pre><code>&lt;?php
  
  $url = "http://localhost/test.php";
  
  $rand_val = rand(1000, 9999);
  
  echo "&lt;iframe name='dynamicload' src='{$url}?rand_val={$rand_val}'&gt;&lt;/iframe&gt;";
  
  ?&gt;
  </code></pre>