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Why is firefox running so slow lately?


For the past month, maybe longer, Firefox has been extremely slow. The videos are also delayed. I have used firefox for many years and now I am disappointed with this browser. I cleared the cache and cookies, twice within a week. No improvement. I've been using Safari for my videos, but all my bookmarks are on firefox. How can we fix this problem? Whats going on ??

Chosen solution

Hi mariebm56,

Sounds like an irritating issue! Not to worry, we've got you covered. Have you looked at our performance troubleshooting section? There is a lot of good information in there that should help. It could be any number of things that are causing the slowness and clearing the cache is really just the tip of the iceberg for troubleshooting. I'd suggest that you try all the steps listed in those troubleshooting articles just to be safe.

Hopefully this helps!

Read this answer in context 9

Additional System Details

Sites Affected


Installed Plug-ins

  • Google Talk Plugin Video Accelerator version:
  • Version
  • Shockwave Flash 10.3 r183
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in web pages. For more information, visit the QuickTime Web site.
  • 5.0.61118.0
  • The Google Earth Plugin allows you to view 3D imagery and terrain in your web browser.
  • Java Plug-In 2 for NPAPI Browsers
  • http://www.facebook.com/fbplugin/
  • The Flip4Mac WMV Plugin allows you to view Windows Media content using QuickTime.
  • iPhoto6


  • User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.5; rv:11.0) Gecko/20100101 Firefox/11.0

More Information

sidsacc 0 solutions 1 answers

Firefox memory leak has remain unresolved for years after years. Now seems it won't be fixed ever! Issues:-

  • Start-up time is way slower when compared to chrome.
  • Page rendering time is also slow in most of the cases (however rendering is more accurate/ has better extension support, as against chrome).
  • Memory consumption is very very high and keeps growing over a period of time (lot better over Chrome, however IE and Opera stand way ahead using less)
  • If Firefox(with multiple opened TABS) is left unused for long(say overnight) then re-opening existing tabs takes a lot time.(This issue is not there in Chrome, but IE does have the same issue).

For now, I am switching to Chrome until a major update comes into picture.

Bank Heist 0 solutions 3 answers

I reset Firefox and at first I was kind of worried I would lose everything mainly bookmarks and after reading about it to be honest it works like a charm and so far since the painless reset things have really been moving a lot faster and video's are streaming so much better and just overall Firefox is faster somewhat like the old days.

I really hope it continues like this and I figure it wasn't Firefox at all but maybe a ad-on was conflicting with it. I'm not sure which one if in fact that's what it was but I installed the ad-ons I can't live without and still I'm good so maybe try to reset Firefox and the great thing is if it doesn't appear to be running any better or the same simply revert it back to the way Firefox was before the reset.

I really like Firefox and hands down the best browser out there maybe not the fastest browser as I have only read that numerous times and can't back that statement up because I don't want to try another one to see lol.