Ext version tested:
  • Ext 4.1.0
Browser versions tested against:
  • IE9
DOCTYPE tested against:
  • <!DOCTYPE html>

Below is a simple page that demonstrates a memory leak in Internet Explorer version 9. On initial load, the page consumes approximately 51MB of memory. After hundreds of page refreshes (F5), the page consumes 78MB of memory.

The page simply loads the ExtJS library and display a div, but there is gradual memory leak accumulation after each page refresh. The memory is not freed until the browser is closed.

This issue appears to only affect Internet Explorer.

Steps to reproduce the problem:
  1. Open the page (note the memory usage)
  2. Refresh the page (F5) several hundred times, and notice the memory usage gradually increase
The result that was expected:

  • The memory is freed after each page refresh.
The result that occurs instead:
  • Memory usage gradually increases and is not freed until the browser is closed.
Test Case:
<!DOCTYPE html><html>


<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />

<meta http-equiv="cache-control" content="no-cache" />

<meta http-equiv="pragma" content="no-cache" />

<script type="text/javascript" src="extjs-4.1.0/ext-all-debug-w-comments.js"></script>



<div>Leak Test</div>


Additional CSS used:
  • none
Operating System:
  • Windows 7 Professional, Service Pack 1