The big news this week was the release of Firefox 15, which prevents most add-on memory leaks. As a consequence, we were able to close open bug reports for several add-ons that no longer leak: Firebug (yay!), Enter Selects, LinkResolve, We-Care Reminder, Restartless Restart + SmartSearch (the leak happened only when both were installed).
Although Firefox 15 prevents most zombie compartment leaks, some remain.
- Scriptish still leaks. Scriptish is a GreaseMonkey fork. Fortunately it has many fewer users than GreaseMonkey.
- Speed Dial creates a zombie compartment when adding a new page to the speed dial. This was only just reported, so we don’t yet know if it pre-dated Firefox 15 or not.
I haven’t heard much feedback about the release from actual users. This is probably a good thing, as users are much more likely to notice and report problems than improvements. One thing that has cropped up is that a small number of add-ons have had their functionality adversely affected by the change, i.e. they were accessing compartments for a page after the page has been closed.
- This caused certain GreaseMonkey scripts to leak badly. This has now been fixed.
- AutoPager’s main functionality is now broken. On the upside, it no longer leaks. AutoPager’s author hasn’t been responsive for the past five months, unfortunately.
- TabMix Plus is popping up some error windows that it shouldn’t.
- Two users with many add-ons installed have reported increased memory consumption. The add-on(s) responsible haven’t been identified yet.
If you have any additional add-ons that you think have been adversely affected by Firefox 15, open the error console and use the “filter” search box in the top right-hand corner to look for a message that says “TypeError: can’t access dead object” — that’s the message that indicates an add-on is trying to access memory via a reference that Firefox 15 has pre-emptively cut. Please report any problems in Bugzilla and put “[MemShrink]” in the whiteboard field.
On a related note, the discussion of Firefox 15’s release on various tech sites prompted me to debunk the common misconception that Mozilla claims “this is the release that fixes the memory leaks” on every release.
Brian Nicholson roughly halved the amount of memory used in Firefox Mobile’s page readability check. (This wasn’t actually marked as a MemShrink bug; I just chanced upon it today when looking at TBPL.)
Nick Cameron fixed a small, obscure leak.
For quite a while now we’ve had various people say that Google Reader creates lots of windows and/or compartments and causes Firefox’s memory consumption to gradually increase when it’s open for a long time. This may only happen if you are signed into a Google+ account. It feels like it’s a problem with Google Reader itself rather than Firefox, and a Google Reader engineer is CC’d on the bug report, but no progress has been made, and the reported symptoms are on the vague side.
If you have experienced this, we’d love to hear your feedback in the bug report. In particular, as always, reliable steps to reproduce would make a big difference.
Here are the current bug counts.
- P1: 22 (-3/+1)
- P2: 90 (-2/+3)
- P3: 96 (-9/+7)
- Unprioritized: 2 (-2/+2)
Forward progress! Good to see.