That only helps with those that have AVG, and honestly if you have to disable your security to get it working, that is another problem.

Just another note that the problem is still present on Firefox 5.0 (windows 7 x64). So far the only solution I've found is to install this addon and activate it:

https://addons.mozilla.org/en-US/firefox/addon/memory-fox/

I'm not thrilled about having to install an addon just to have my browser 's memory grow to 1.6 GB and become unstable but its either use this or dump Firefox all together and switch to Google Chrome.

I registered on these forums just to talk about this issue. Computer specs for reference will be posted at the bottom.

I love Firefox. Been using it for a very long time. Not only has it saved me many headaches by installing it on computers I fix and telling people to stop using I.E. to prevent viruses, but it's the only browser that has the only add-on I use. NoScript.

I noticed one day that my browser was acting real slow using version 3.6. I open up the process manager to see over 1 Gig in memory being used. That is absolutely not acceptable. So I decided to look for a new browser.

After several hours of research and testing other browsers, I learned that none of them have an add-on exactly like NoScript. I almost switched to Chrome, but that held me back. What I also learned is that there were new versions of Firefox, 4.0 and a beta version of 5. With that knowledge in hand, my flame for Firefox lit anew. So I choose to download the beta version and see if the problem was fixed.

Beta five blew me away. Huge improvement over 3.6 in terms of UI design. I thought my worries were over. But alas, after a half of day of usage I found the memory leak to continue. I was disheartened.

Even as I am writing this, the Firefox process is eating more and more memory than when I first came here. Started at 123, 000 K when I first started typing and now at 240, 000 K, with no signs of stopping. Again, no add-ons except for NoScript, and only two other tabs open other then this website. Reddit.com tab, and a Google search tab.

Seeing no official response to this, and with the knowledge that this has been going on for years, I guess it's time for me to hang the Fox up. Regretfully, I will continue my search for a new browser.

Window 7 Home Premium 64x Bit Edition

4 Gig DDR2 (PC2-6400) Avant Technology Memory

E5400 Dual Core CPU 2.7 (O.C. 3.7) Ghz

I'm rather bummed that Beta 5 is not showing any improvements. I'm sorry to say that until this is fixed, Firefox is taken off of both my Mac and PC, and Safari and Chrome are my main browsers now, until I find something better...

I really wish someone from the Firefox developer's group would comment here, having over 600 people with this issue is no small matter.

I agree with the OP. This is a shocking bug to see in a browser that has been known for memory problems since it first came out. I've been an ardent Firefox fan since 0.x versions, and it has been my browser of choice for development since early release versions.

But this has got to stop. Doing nothing causes it to chew up memory. Going to different web pages makes it chew them up faster. But I can make it eat up gobs of memory really fast simply by using setInterval to call a function every few seconds that checks whether an object exists. Setting no variables, mind you, just checking for the existence of a simple object. And when the object is detected, the interval ID is cleared.

At about 800 mb the browser becomes unusable and I have to kill it with fire.

Well it looks like they are going to start looking into this: http://news.slashdot.org/story/11/06/10/2125227/Mozilla-MemShrink-Set-To-Fix-Firefox-Memory

Unfortunately it was too late for me. I just switched everything over too Google Chrome and haven't looked back.

I hope that this gets fixed for you guys. I'm still going stick with Thunderbird and Songbird.

They keep saying it every year that they are going to fix this bug... with each revision, every major upgrade, etc... I'll believe it when I see it.

• Monitor memory usage of the Firefox process. (MAC = Activity Monitor / PC = Task Manager)

• Open several windows with several tabs of all different url's (websites).

• Check your Extensions and Plugins: Tools -> Add-ons.

• While memory usage starts climbing, start to disable your add-ons one-by-one until memory ramping stops. (Restarts are required, Use Session Manager to reload all open windows and tabs.)

• If memory usage does not stop ramping up after all Add-ons are disabled, begin closing tabs one-by-one. Odds are you have a bad site or two loaded.

• Once you are positive that bad sites are removed and memory usage is stable, begin re-activating your Add-ons until you find which one(s) are causing trouble.

• Uninstall & report misbehaving Add-ons and websites to their authors.

In my experience with FF5 and previous versions, both extensions and websites were to blame.

Best, RJBradlow

@ tekwyzrd... I suppose if after so many years of DUI accidents involving any given car make... we should avoid those vehicles, Right? After all; It's not the fault of the P.O.S. inside driving it, is it? No, it must be the car maker's fault.

Browsers are told how and what to do by their content, and Add-ons manipulate your Browser appearance and functionality much in the same way drivers do with vehicles.

To break it down further... the browser and the car are both vessels for which other people control and modify. Check your Add-on Extensions and Plug-ins; Friends don't let friends... Drive, er, Surf ______

Cyberpawz - If you are still around -get rid of your Fun Web Products and you'll notice a dramatic improvement.

For other readers the same applies to MyWebSearch, MindSpark, Conduit Engine, Ask toolbar. If you don't know how or why you have these, that is Definition 1 and 2 of malware.

As a general point users may like to know that

• Firefox 4 did seem to have specific problems with memory, but some of thes problems have been cured in later versions, (Firefox 4 is no longer supported so it should not be used)
• Firefox developers started a project recently and have been making, and continue to make changes in how Firefox handles memory, and the tools available to help diagnose and reduce these problems. (Those interested in the technicalities may wish to glance at the blog articles by this developer http://blog.mozilla.com/nnethercote/2011/07/20/zombie-compartments-recognize-and-report-them-stop-the-screaming/ )

Unfortunately Firefox has the advantage of being able to be used with a vast array of other software, not surprisingly some of the combinations and uses to which they are put can cause problems. I would tend to agree the memory problems should have received attention earlier, but that is now happening, and lets not forget the software is open source and free.

Honestly I had no extensions except an antivirus. Also I was programming websites using strict HTML and CSS. These are not intensive languages.

My plugins were a non issue here. So try to explain to me why my firefox was acting more like a firehog than a speed demon?

Cyberpawz Your More system details show in your Plug-ins "Fun Web Products Plugin Stub for 32-bit Windows" . This is an issue.

As I've said before, I have the basics set up for plugins... starting with CSS and HTML do not require use of that plugin.