First, try to reset Firefox. Refresh Firefox - reset add-ons and settings. This simple step will eliminate many Firefox problems with only one click.

A few other basic trouble shooting things you can try is this: Run all Windows Updates, install all needed service packs, etc.

Update your graphics driver (Firefox uses your graphics card for some rendering, and an out of date graphics card driver can cause problems. Upgrade your graphics drivers to use hardware acceleration and WebGL

Update all your plugins (Flash, Java, etc.): http://www.mozilla.org/plugincheck/.

Download and Install MalwareBytes Anti-Malware, run a full Scan. http://www.malwarebytes.org/. This helps check that there are no viruses on your computer causing issues. You can uninstall this program after you clean off any infections.

According to VirusTotal.com, the latest stable version of firefox (14.0.1) is infected with a trojan: TROJ_GEN.F47V0719. I checked the en-US version only.

No the latest version of Firefox is not infected. Either you have a virus on your computer, ir the scan you used is reporting a false positive (most likely). please reporr this to them.

Only TrendMicro-HouseCall has made the claim for days now as an example https://www.virustotal.com/file/e682be3ba4e97c8ecc266e7d17bc69d74d8698467be992c9b0c26287e619af3c/analysis/

I agree that is very likely a false positive as some antivirus apps have made such claims after a new Firefox update over the years and was usually corrected by a antivirus definition update in short order.

Over on a post @ http://forums.mozillazine.org/viewtopic.php?f=23&t=2506211 they have discovered that the latest update to the add-on Search By Image (by Google) version 1.0.6 is causing a HUGE MAX CPU use over time.

I had the same problem until i disabled that add-on.

There has been a Bugzilla report made as well

Being a reformed black hat with 30+ years of coding experience I can see why there are serious resource issues with the latest update. FYI: The Search By Image Google add-on is not and never has been installed on any of my machines. The problem(s) are due to the fact that apparently the programmers have no idea how to resolve the issue(s) with the latest update since they blame the problems on everything but their inability to write good code. The issue has ALWAYS BEEN the inability to properly handle plug-ins and add-ons - images and Adobe Flash in particular. While some will wait and hope that the problems get fixed, I am not as I have lost all my faith in Mozilla and Firefox. No other browser has the problems that Firefox has been seemingly accumulating with each update. I have Safari, IE 9 & 10 (Win 8 on a beta machine), Chrome and Opera installed and never experience any resource issues with them. Start up Firefox and the CPU gets maxed almost immediately. For me the solution is simple: Don't use Firefox.

Hi KoloheWiz, were you just coming by to suggest not using Firefox or did you have a question?

In case you are having issues with Flash, there are some compatibility issues between the latest Flash player and some Firefox add-ons or settings. Could you see whether anything in this article helps: Flash 11.3 doesn't load video in Firefox.

If you run Windows Vista or Windows 7, you might also consider disabling the new protected mode in Flash 11.3, since that feature is currently being debugged. See this support article from Adobe under the heading "Last Resort": Adobe Forums: How do I troubleshoot Flash Player's protected mode for Firefox?

As for CPU usage, this depends on individual configurations. For troubleshooting assistance with that, please start a new thread and list your system and extension information.

https://support.mozilla.org/en-US/questions/new/desktop

Gee... Based on what was written, what do you think? Here's a hint: Read the last 3 words in the post. However, if you really want me to ask a question, I will: Why can't the coders of Firefox even send functional verification links in emails? Considering something as simple as that appears to be an obstacle debugging a poorly coded browser is most likely an insurmountable challenge.

Hi KoloheWiz, what was the problem with the link in the email? Obviously the forum software is completely distinct from the browser code, and your feedback on problems with the forum software may be helpful to others.

The link was to confirm a change in my email address. Unfortunately, it was a useless link that only produced a "Page Not Found" error. I tried several more times and the result was the same even though I was sent new links. If an organization can't do something as simple as provide a usable link in an email, how can they be expected to produce a reliable web browser?

After spending some hours going over the code for the latest version I have discovered some image handling errors that may be part of the CPU overuse issue. In fact, even if plug-in container.exe is closed (which also closes the two Flash 11.3 instances that are running) the maxed out CPU issue still exists. This is what made me curious as to the real cause of the problem. I opened a couple of my IDE programs and started digging through the many lines of code looking for particular expressions. There seemed to be some conflicts with the way images are handled on the various types of web pages - html (incl. HTML5), asp, aspx, jsp, etc. - and CSS schemas. If that is of any help to the programmers there at Mozilla, then I am happy to be of assistance. In the meantime, I will continue to avoid using Firefox at all costs and recommend that my business clients, family and friends do the same. One business client actually overheated his CPU because of this issue. I tested this as well by monitoring the CPU temp while running Firefox and nothing else other than the background drivers and security software and seeing that the CPU was maxed at 100% for both cores. Sure enough, the temperature continued to rise despite the fan running at its max speed. This is a serious issue that Mozilla needs to not only fix but warn users about until it is fixed.

What kind of images are causing the problems?

Did you check that it isn't caused by JavaScript that is running on those pages?

I have the same problem, and I love Firefox, but this is really bad:

Firefox indicates close to 100% CPU in Windows task manager

EXAMPLE: I do an image search on Google, 1st page would load in reasonable time but the CPU will stay at 99% and I cannot scroll down to view more images until a minute passes. Then I can view them until I scroll down again. While I wait for images to be rendered Firefox is completely frozen.

• I am running Windows XP with latest updates, and Firefox 14.0.1

• I use Microsoft Security essentials - I don't think I have a virus.

• For Firefox browsing options I have ticked "Use hardware acceleration when available", no smooth scrolling or autoscrolling.

• I have only 4 Add-ons: Adobe Acrobat, Java Platform, Quicktime, Shockwave Flash. They are either up to date or not very old.

• Internet Explorer does not have this problem on the same PC, neither does Firefox on Linux (Ubuntu) on the same PC, so its not the hardware.

• I have recently done a registry clean-up, so I don't think have rubbish in there.

Any help welcome. If you want more info let me know.

PS: I have disabled Javascript as an option in Firefox, now this provides a temporary solution. My Google image searches are now on a page by page basis and I can click on consecutive pages and the images are rendered quickly. Firefox shows I have Java(TM) Platform SE 7 U5 10.5.1.255

Hi beesblaas, have you tried unchecking graphics hardware acceleration? Since this feature was added to Firefox, it has gradually improved, but there still are a few glitches.

Thanks for the suggestion. I un-checked all tick-boxes in:

Tools> Options > Advanced > Browsing.

Firefox.exe still hits 99% CPU power in the Windows Task Manager.

However if I disable Javascript (Tools > Options > Content) it is OK. The problem is that I loose Javascript features and for some websites.

Another issue: Every time I in-check Javascript, next time I start Firefox it is checked again.