Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Why is Firefox ESR 52.4.1 using 100% of my CPU even when nothing is loading? This is the worst I've seen in years.

more options

Even on this page, Firefox freezes and stalls. When I check, it uses all my CPU. The problem is worse than even, even with a new install. Yes, this an old computer running Windows XP, but I'm not seeing the issue with any other software or browser. I would hate to switch browsers until I can afford a new computer.

Nothing in any of the support topics has helped or mitigated the problem.

Even on this page, Firefox freezes and stalls. When I check, it uses all my CPU. The problem is worse than even, even with a new install. Yes, this an old computer running Windows XP, but I'm not seeing the issue with any other software or browser. I would hate to switch browsers until I can afford a new computer. Nothing in any of the support topics has helped or mitigated the problem.

All Replies (6)

more options

DrStrange10150 said

Also, Crash Reporter has not been able to send a report to Mozilla when Firefox crashes for years.

Not all Crash Reports are submitted to the Reports server, so as to not overload the system. Keep in mind that the primary purpose of the Crash Reporter is to help the developers improve Firefox so that is doesn't crash; helping the user fix their crashes comes in as secondary purpose.

As far as accumulating a large number of crash reports that weren't ever submitted, it could be based upon my inexpert observations over the years, that the more reports which aren't automatically submitted to Mozilla, the greater chance that they WON'T be submitted automatically.

Clean that cache or accumulation out sometime and see if more of your rashes do get submitted automatically; and thus verify my observations in that regard. I think there is a causal relationship between that accumulation of crash reports and a decrease in crash reports not being automatically submitted in the future.


You can submit any UN-submitted crash report at any time thru the about:crashes window by clicking on a report. Then once it is submitted you can click on it again to view that crash report, after it gets loaded to the server that displays those reports. Sometimes it does take as much as 5 minutes to locate the specific report due to the amount of data which has been submitted. The reports seem to come up faster when they have been have been sitting for awhile; so manual submissions may take time to get transferred the the "viewing server", or at least that has been my experience.

more options

A lot of plug ins are disabled. There is nothing on the page to let me remove any I would like to anyway. In fact, the "Add-ons Manager" and "Plugins" pages don't even work properly because of the CPU usage issues.

I've tried "Safe Mode" and a clean install and it makes no difference. In fact, I cannot run any forms, watch videos, fill out applications, without major delays that never used to exist.

Right now, this is the only tab open and it is using 98% of my CPU with over 1,000,000K in Private Bytes.

more options

DrStrange10150 said

A lot of plug ins are disabled. There is nothing on the page to let me remove any I would like to anyway.

Plugins are from programs that Firefox finds already on your system.

An extension without a Remove button is really a plugin. The only way to remove a plugin is to remove its program from your system. However, you can disable extensions and plugins if you want.

more options

Plugins are installed on your system and not in Firefox like Extensions and complete Themes are so you cannot remove Plugins directly in Firefox. You can type about:plugins in the Location (address) bar to see where the NPAPI Plugins your Firefox is making use of is located on system.

Endret av James

more options

Are all the CPU spikes random you mentioned?

more options

Various plug-ins and extensions disabled or removed. No effect. Still cannot find some. A few that I know have been removed are still listed after restarting FF, but are no longer listed anywhere on my computer.

CPU spikes are not random. They always happen. Right now, this is the only tab open and CPU usage is 98% and the Private Bytes is increasing as the table stays open.

  1. 1
  2. 2