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Firefox 21 CPU usage problems

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I made the stupid mistake of allowing Firefox 21 to install and now must be a guinea pig or part of your User Acceptance Testing, well I don't accept.

Since upgrading there is a pattern, Firefox loads and starts to work OK at first, then after several tabs are open and for no apparent reason it starts using a constant 25% of CPU, at the same time no websites work properly, even Google takes 15 seconds to load.

So I terminate the service and reload Firefox, it then starts to work OK for a while but soon starts the same behaviour all over again. No particular site seems to be responsible and it happens over and over.

I also noticed that the memory seems to keep increasing even if I am not loading any new sites or even if I have Firefox in the background.

I am not going to re-install, I lost thousands of structured bookmarks last time that happened.

Why can't you just release software that works.

None of my plugins seem to have any problem, it seems to just be Firefox.

Is anyone else experiencing this?

I made the stupid mistake of allowing Firefox 21 to install and now must be a guinea pig or part of your User Acceptance Testing, well I don't accept. Since upgrading there is a pattern, Firefox loads and starts to work OK at first, then after several tabs are open and for no apparent reason it starts using a constant 25% of CPU, at the same time no websites work properly, even Google takes 15 seconds to load. So I terminate the service and reload Firefox, it then starts to work OK for a while but soon starts the same behaviour all over again. No particular site seems to be responsible and it happens over and over. I also noticed that the memory seems to keep increasing even if I am not loading any new sites or even if I have Firefox in the background. I am not going to re-install, I lost thousands of structured bookmarks last time that happened. Why can't you just release software that works. None of my plugins seem to have any problem, it seems to just be Firefox. Is anyone else experiencing this?

All Replies (5)

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hello, please see if you can replicate this problem when you launch firefox in safe mode once or when you reset firefox...

Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

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see the suggestions here:

Firefox uses too much memory or CPU resources - How to fix

... and let us know if it helped.

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It is not a problem fixed by uses too much RAM, it is only using 500mb and counting on an 8gb system, I find it usually can't handle more than 1.6gb and then a terminate and restart will recover and work.

I am happy to disable all addons but not to run the reset option, that will screw with a config that I have spend YEARS building, one that is part of the way I work. It took MONTHS to get my system back last time I had to do this and lost productivity for ages.

This is why I say I was STUPID to update to V21,

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I noticed your system has Next Generation Java Plug-in 10.9.2 for Mozilla browsers, which is as far as I know outdated. Please check if this plugin and all other plugins you have are up-to-date. To do this, go to the Mozilla Plugin Check site.

Once you're there, the site will check if all your plugins have the latest versions. If you see plugins in the list that have a yellow Update button or a red Update now button, please update these immediately.

To do so, please click each red or yellow button. Then you should see a site that allows you to download the latest version. Double-click the downloaded file to start the installation and follow the steps mentioned in the installation procedure.

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This is also a problem on Firefox 23. CPU reaches 100% on starting Firefox and when opening a number of tabs, or just a few or one or two. Firefox then locks up and it is impossible to scroll, open or close tabs/windows while CPU is at 100%.

Firefox do not seem to acknowledge that there is a problem here. This started around version 19 and has been getting worse with each subsequent version. Is it simply that Firefox is becoming more resource hungry with each iteration?