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Version 20, Memory Leak Still?


I've been using Firefox since well, lets just say long enough... Version 20 for the Mac seems to not have fixed any bugs or memory leaks.

One of the "fixes" is to restart Firefox, which is the only "fix" that works, but this really isn't a fix, this is a stopgap situation, in where you release the memory by closing it...

Are there other people with this same situation? My Firefox uses with nothing in the main page except google.com, if it's open for over 24 hours over 1GB of ram... 2 GB in 48 hours, etc...

The most Firefox has ever used was 5GB before I shut it down, now I know, restarting Firefox seems to stop this from happening, but as I said, this is a stopgap, there is something inside Firefox that makes this happen.

Is there anything in the future that will fix this issue, or is Firefox going to be forever a Memory Hog worse than Microsoft Office?

Modified by Cyberpawz

Additional System Details


  • User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_3) AppleWebKit/536.28.10 (KHTML, like Gecko) Version/6.0.3 Safari/536.28.10

More Information

Uncle_Killy 0 solutions 3 answers

Well during the play of 8 Ball Pool I've watch occasionally YouTube, surfing...but anyhow, memory usage is increasing during surfing, but not dicreasing within shuting down certain tabs.


I don' t know. Within next surf, I'll post results of memory usage. But since I'm a dummy :D, you're gonna have to tell what I'm going to do, step by step.

Uncle_Killy 0 solutions 3 answers

I have figured out what (which pages) is loading so much of RAM.

One of those TUMBLR.COM pages with constant images loading, you know those pages that seems like they don't have an end.

But within closing of that specific TAB with one of those pages, memory which FF is using is not DICREASING.

Sorry for bad english. :D

  • Top 10 Contributor
2345 solutions 20793 answers

Hi Uncle_Killy, that's a helpful observation.

In earlier versions, scripts that updated the URLs in an image "slide show" faster than Firefox could download the images led Firefox to keep image data in its memory cache that it could/should have discarded, using more and more memory. I looked at a page demonstrating this more than six years ago. A bug was logged into the tracking system, but I don't see any recent activity on it.

Note about the bug tracking system: if forum members can contribute to the development, please feel free to pitch in. Otherwise, it's generally not helpful to add comments to bugs (unless there is a call for test cases), but you can register on the Bugzilla site and "vote" for them to be fixed. See:

  • Top 25 Contributor
  • Moderator
622 solutions 7998 answers

edit I wrote this before I saw your comment about images and Jscher's reply

Maybe you have found a zombie !
(Don't even bother trying to follow those instructions.)

I will make sure Noah is aware of your post, he is in direct contact with developers and so will know if and what information is useful.


  1. Would you like to start your own thread please
    1. Use /questions/new
    2. Try to follow the prompts to include full troubleshooting information
    3. Please post back here again when you have done so
  2. And maybe this is something you could try, if you try, or have problems mention it in your other new thread
    1. Navigate to about:memory by keying that into the address bar and clicking the green arrowhead
    2. You will get a page that has buttons at the top and gives information about Firefox memory use. Note many items gives some sort of information as you mousover
    3. Click the [Measure] button, things may freeze for a while but then it produces a rather complicated looking report. We may need some of this later, but don't worry about that now.
    4. Click on some of the free memory buttons they should reduce your memory usage.
    5. If you look at your favourite memory reporter when your memory use is high and click the button [Minimise memory usage] it may actually work and reduce your memory usage.

The above is not a proper solution to your problem but it

  • may help relieve your immediate problems
  • is an introduction to an advanced tool that is capable of providing useful information.

Modified by John99