Closed Bug 324793 Opened 15 years ago Closed 9 years ago

[mlk] Memory Leak with IE Tab extension


(Firefox :: General, defect)

Windows 2000
Not set





(Reporter: stevee, Unassigned)



(Keywords: memory-leak, Whiteboard: [MemShrink])

Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9a1) Gecko/20060125 Firefox/1.6a1 ID:2006012517

IE Tab 1.0.7 extension:

Homepage is about:blank.
No websurfing is required to show the leak

1. New profile
2. Install IE Tab 1.0.7 extension (currently 7th most popular extension with 63045  downloads)
3. Restart firefox
4. Close firefox reports:
Leaked inner window 1d6ceb8 (outer 1800818) at address 1d6ceb8.
 ... with URI "chrome://browser/content/browser.xul".
Leaked outer window 1800818 at address 1800818.
Leaked 2 out of 6 DOM Windows
Leaked 0 out of 24 documents
Leaked 0 out of 3 docshells
The extension author might need help:
It should be noted that when actually using IETab to view IE pages in firefox, even more leaks are reported.
Summary: [mlk] Memory Leak with IE Tab 1.0.7 extension → [mlk] Memory Leak with IE Tab 1.0.7 extension, even when not using it for any tabs
according to IE Tab's homepage at the memory leak has been fixed as of version 1.3.*

Im not sure if this is true or not, but I thought I should update the bug report to reflect this information
Thanks WildCide.. I've re-examined this problem and so changed the bug description. Things have gotten better, but this still leaks.

Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv: Gecko/2007071603 BonEcho/

1. New profile, start firefox
2. Install IE Tab from
3. Restart Firefox to complete installation
4. Close firefox and start it back up with leak logging enabled
5. Homepage should be something like
6. Notice the new icon at the bottom right of the status bar. Click it to change to the IE rendering engine.
7. Page reloads, rendered by IE.
8. Close firefox, analyse leak log

Leaked inner window 2bb4970 (outer 24db988) at address 2bb4970.
 ... with URI "chrome://ietab/content/reloaded.html?url=http://www.mozilla-europ".
Leaked document at address 1c21e58.
 ... with URI "chrome://ietab/content/reloaded.html?url=http://www.mozilla-europ".
 ... with URI "jar:file:///C:/Documents%20and%20Settings/Ste/Application%20Data/
Leaked 1 out of 8 DOM Windows
Leaked 1 out of 37 documents
Leaked 0 out of 3 docshells

If you click the icon three times (So the rendering engine goes: IE, Firefox, IE) and then close and analyse the leak-log, you get:
Leaked 2 out of 10 DOM Windows
Leaked 2 out of 39 documents
Leaked 0 out of 3 docshells

So it looks like every time you choose to render a page in firefox using the IE rendering engine, a DOM Window and a Document is leaked. If you right click on a page and choose "View page in ext. app" (IE) then no leak is reported.
Summary: [mlk] Memory Leak with IE Tab 1.0.7 extension, even when not using it for any tabs → [mlk] Memory Leak with IE Tab extension
Comment 4 also applies to the dev build (IE Tab
Flags: blocking-firefox3?
Is there any evidence that this is Gecko 1.9 / Firefox 3 leaking memory and not something being done in the extension? Until there is, this isn't a blocker.
Flags: blocking-firefox3? → blocking-firefox3-
> Can someone help me understand why this is filed under Mozilla's Bugzilla

Because it might be a Gecko bug.  That said, it's not obvious that it is, as comment 6 pointed out.  Someone would need to debug the leak to make sure.
DEBUG_CC doesn't give any useful information other than saying that there is 1 outstanding reference to a window that is expected to be garbage and 1 outstanding reference to a document (in both cases, 1 total references, 0 known).  That implies it's not a leak from JavaScript; it could be a reference counting leak either in IETab's binary part or in Mozilla code that IETab triggers.  I've been unable to get XPCOM_MEM_REFCNT_LOG or trace-malloc to work; not sure why not.
What about Coral IE Tab? Does it leak as well?
Whiteboard: [MemShrink]
According to it doesn't work with FF4+.  There is an IE Tab 2 add-on.  I think we can close this bug.
Closed: 9 years ago
Resolution: --- → INCOMPLETE
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