When you work  with the Agent Console (version 9.x), you might receive the following warning:

"Warning: Unresponsive script
A script on this page may be busy or it may have stopped responding.
You can stop the script now, or you can continue to see if the script will complete."

Possible cause:

Agent Console uses the Firefox engine to display the visitors pages in the PageViewer tab.  
The default time-out for JavaScript execution has been set to 5 seconds (10 seconds in later versions of Firefox), causing the browser to issue this message whenever a script exceeds this time-out.

If you receive this warning message, click Continue.
In order to prevent this warning from being displayed again,  change the default time-out for the JavaScript execution to a longer period of time (20-30 seconds)


To  change the time-out period for the JavaScript execution:
  1. Open a new page/tab
  2. Enter the configuration page by typing about:config into the URL field and press Enter
  3. In the about:config page, search for the preference dom.max_script_run_time, and double-click on it
  4. In the Enter integer value prompt, type the requested number of seconds (20 or 30)
  5. Click OK
Increase Timeout