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I cannot watch Flash vids because Firefox uses too much CPU.


Firefox has become untenable because it uses too much CPU and disrupts Flash videos.

I've tried disabling or changing the values of plugins. Installing older versions. Nothing helps. It just sucks. It makes me want to pull someone's lungs out.

Chosen solution

Additional System Details

Installed Plug-ins

  • Default Plug-in
  • Shockwave Flash 11.1 r102
  • iTunes Detector Plug-in
  • DivX Plus Web Player version
  • DivX VOD Helper Plug-in
  • Picasa plugin
  • Windows Presentation Foundation (WPF) plug-in for Mozilla browsers
  • Adobe PDF Plug-In For Firefox and Netscape 10.1.1


  • User Agent: Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv: Gecko/20091102 Firefox/3.5.5 ( .NET CLR 3.5.30729; .NET4.0C)

More Information

I have Firefox 3.5.5. Windows Vista.

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3202 solutions 24448 answers

Chosen Solution

Update to Firefox 8.0.1 - http://www.mozilla.com/en-US/firefox/

kenkw 0 solutions 1 answers

I just installed upgraded to firefox 8.01 on my netbook. firefox 8.01 uses much more cpu than the earlier version of firefox and now just scrolling down the screen slows the computer to a crawl or to a momentarily stop. I have all my plugins, extensions, etc turned off and I also tried safe-mode with the same results. This is totally unacceptable. I thought I may have been infected with malware but similar cpu usage occurs on my laptop and desktop. I just didn't notice because before those CPUs/GPUs are much beefier.

Helpful Reply

Everyone has this problem, since Firefox rigged one of its Plug-ins (something to do with crash reports) about 06 months ago, to max out CPU, thereby sabotaging computer performance (including Flash videos).

Why or how they haven't fixed it before now strains belief. I have seen the same complaint everywhere. It is a major fuck-up. People want to abandon Firefox in droves, except that none of the other browsers have decent add-ons like pop-up blocker.

Sort it out, Firefox.