Information
Firefox can be configured to prevent scripts from closing browser windows.
Preventing an arbitrary web site from closing the browser window will reduce the probability of a user losing work or state being performed in another tab within the same window.
Solution
Perform the following procedure:
* Open the mozilla.cfg file in the installation directory with a text editor
* Add the following lines to mozilla.cfg:
lockPref("dom.allow_scripts_to_close_windows", false);