Take the 2-minute tour ×  Can I rely on the window unload event
to be triggered when a user closes a tab/window/browser?   Found
a list of what triggers the unload event in IE.
http://msdn.microsoft.com/en-us/library/ms536973%28VS.85%29.aspx
I would like to know in which edge cases the unload event won't
be triggered.  share|improve this question youd have to give
more use case - what is it that you want to achieve with the
unload? There might be other ways to implement that feature
other than unload events. –  Chii Oct 20 '09 at 13:34 add
comment  2 Answers  You will likely want to use the
"onbeforeunload" event too, it provides more control than the
"onunload" event.  That said, be aware that: Opera doesn’t fire
the unload event when the browser refreshes the page, or uses
the back/forward buttons to browse off of the page. What’s
worse, Opera never fires the onbeforeunload event. Thus if you
are supporting Opera - be aware of these issues.  share|improve
this answer Thanks for the Opera info. –  bhseo Oct