Open Bug 510945 Opened 14 years ago Updated 6 months ago

'onbeforeunload' code does not submit html form that is to be sent from an iframe


(Firefox :: File Handling, defect)

Windows XP





(Reporter: ChristopherBalz, Unassigned)




User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv: Gecko/20090729 Firefox/3.5.2
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv: Gecko/20090729 Firefox/3.5.2

It appears that 'beforeunload' does not make sure that the action it 
commanded in an iframe completes before the parent window of the iframe has 
unloaded, destroying the iframe.  IE does get the behavior right.

Due to this bug, sales lead data is not captured from the pages following 
this one when users who have entered an international address navigate away 
or close browser (but works perfectly on IE, as noted above):

Reproducible: Always

Steps to Reproduce:
1. Go to

2. Set up the web page at the above url so that you can verify the actual 
form posting from the page: Either copy the page and its includes to a 
local server environment where you can change the 'post' url target to a 
server you can monitor, or instrument the browser with a Web proxy (such as 
Charles at  

3. Note that on Firefox the Firefox HttpFox add-on, for example, reports 
that the form submit works, but in fact, the data does not actually get 
sent.  Similar behavior could be encountered for Chrome.

4. Do the Verification Targets at top left on the web page.

Actual Results:  
 Form data should be posted (from iframe) and also submitted via 'get' 
(from main page).

Expected Results:  
 Form data is not posted (but is submitted via 'get').
Note: The point of submitting the form from an iframe is to avoid hijacking the user when s/he wants to go to another page.
Correction: "as noted above" should read, "as noted below":

Other browsers tested:
Add OK or FAIL after other browsers where you have tested this issue:
     Safari 4: Fail
  Firefox 3.x: Fail
         IE 6: Pass
         IE 7: Pass
         IE 8: Pass( IE 8 in Browser Mode: IE 8 Compat View, Doc Mode: IE 7 

Also cf.
If you can make a test case such that I dont have to use any proxy to test, 
I will test and confirm this bug.

I also think this is the expected behaviour.
For everything they are trying to make Async HTTP
As well as fixing this may not be a good idea, we dont want to get stuck 
if for some reason the HTTP post dont complete

So it may get WONTFIXED
Product: Core → Firefox
Severity: normal → S3
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