Just noticed that my Firefox has grown to 1 GB even though I restarted it yesterday. Turned out that I left HttpFox running and forgot about it. As a result I got tons of leaked content compartments.
Steps to reproduce:
* Install HttpFox 0.8.10 from https://addons.mozilla.org/addon/httpfox/.
* After browser restart click the HttpFox icon in the toolbar, click "Start" in the HttpFox bottombar and close it.
* Open http://www.mozilla.org/en-US/firefox/central/ in a new tab and close the tab again.
* Check about:compartments
about:compartments doesn't show http://www.mozilla.org/en-US/firefox/central/ as an active compartment.
http://www.mozilla.org/en-US/firefox/central/ shows up under "User Compartments" and "Ghost Windows". Opening HttpFox bottombar and clearing the entries allows the compartments to be released. Not sure why some sites leak while others don't.
Unfortunately, it is very easy to forget that HttpFox is running. A while ago I argued that it should stop collecting data when its bottombar is closed (http://code.google.com/p/httpfox/issues/detail?id=78) but nothing happened. But even if it keeps collecting data, there is no reason why it should leak compartments.
HttpFox has 107,000 users according to AMO.
The developer has been contacted through AMO.
Created attachment 624532 [details]
Patch that fixes some memory leaks
There are two rather trivial bugs that prevent the important cleanup code from running. I've attached a patch that fixes them. I can't find the author's email address, so I'm posting it here.
Developer chased via info request. I've mentioned the patches contributed and warned that we will downgrade if they don't make an effort to address the leak.
thanks for the patch. new version 0.8.11 was just uploaded and is waiting to be reviewed.