419988 - Firefox leaks when moving mouse from content to toolbar (but not vice versa)

Status: NEW

(Core :: General, defect, P3)

Description

[Justin Dolske [:Dolske]]

Attachment: mac leak log

Ran across this when trying to verify a leak fix in bug 384230 with XPCOM_MEM_LEAK_LOG. Something is leaking when the mouse is moved from content to chrome, but not in the opposite direction. Yeah, it's as weird as that sounds.

1) Create new profile
2) Set default start page to be about:blank
3) Restart browser with XPCOM_MEM_LEAK_LOG set.
4) Click window titlebar to focus the window.

To not leak:
5A) From where you clicked in #4, move the mouse straight down, into the content area and out the bottom of the browser.
6A) Press Command-Q to quit the browser.
7A) No leaks.

To leak:

5B) From where you clicked in #5, move the mouse straight up (so you're over the desktop background)
6B) Carefully move the mouse to the bottom of the window, but to NOT cross over the browser window.
7B) Now move the mouse straight up through the browser window, crossing over content and then the toolbar and then out the window.
8B) Press Command-Q to quit.
9B) Leaks.

I tested various quitting at intermediate points in #5A and #7B. The leak seems to occur as soon as the mouse moves 1 pixel out from the content on top... Hiding either the Navigation Toolbar or Bookbarks Toolbar doesn't stop the leak. Hiding both toolbars does.

Comment 1

[Carsten Book [:Tomcat]]

Confirmed with my Leak Testing Build.

maybe same problem as in bug 419752, logs looks similar.

Comment 2

[Martijn Wargers (dead)]

I seem to get this leak every time on http://www.mozilla.org/projects/minefield/
and the mozilla.org image link or search text input or go button is focused and then I close Firefox. 

Comment 3

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Maybe bug 420803?

Comment 4

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

Tomcat, would be great if you could retest this one and renominate if we're still leaking.

Comment 5

[Sylvestre Ledru [:Sylvestre]]

Moving to p3 because no activity for at least 1 year(s).
See https://github.com/mozilla/bug-handling/blob/master/policy/triage-bugzilla.md#how-do-you-triage for more information