Firefox Community Forum

Firefox is creating very high CPU use with many WebThumbnailExtension Web Connect processes. The processes disappear after shutting down Firefox and other programs that access the internet. Does anyone have an answer on how to prevent this from happening?

MacBook Pro M4 with MacOS Sequoia 15.3.1

I'm finding that firefoxcp isolated web content uses a LOT of memory on my Mac Mini. What can I do about this besides not using Firefox. I like the browser and have been using it since its introduction

When I open one tab on Firefox, my task manager shows multiple programs running along side it. I know some extra processes are needed but this seems like an unusual amount. I have included a screenshot of the tasks that appear. When I try to delete these, they reappear. I have tried various online solutions such as uninstalling and reinstalling, and checking various settings. It is affecting my computer's performance and I am not sure how to solve this. Thank you!

When opening Firefox, Duplicates open but are unseen. I may have 2 tabs open but my task manager tells me there are 14, sometimes 31. What can I do to stop or get rid of the duplicates pages. if I can't I will have to remove Firefox.

Firefox prompted me that my local storage space was insufficient. When I opened the data management page, I found that a particular website's local storage was abnormally large, and some websites were inaccessible or unable to log in. After restarting Firefox, the issue did not reoccur.

I've noticed my GPU fan runs heavily as soon as I open Firefox, and with even just only one browser page open, it runs high speed, where it didn't use to do this. How can I get Firefox from requiring so much of my power. I don't want my electric bill higher just because of a browser. I have a decent GPU good for gaming quality that usually doesn't get clocked enough to cause the fan to turn on and run at high speed unless it's a high-graphics computer game or something. Anything I can do to make the browser demand less on my GPU?

Hello, I am running win 7. Yes and Old computer. When the system is running slow I do a task manager to see what might be causing it.

I have noticed multiple Firefox processes running with 0 CPU usage. What are all those for and do I need them? Can I disable them?

On a separate issue I am getting this rendering error. This may be a Microsoft question, but I thought I'd ask. Error in rendering player Error Code: 400-404 Session Id: k6x4392p (Pls: 35a725dd-3aac-4813-8431-159ebc196c01)

Lastly I did contact support about uninstalling two Firefox programs. I deleted the one you said.

Thanks again for all the help, Irv

I'm tired of trying to find a solution to this problem, you're deaf!

I have been using Firefox since 2003. to avoid writing unnecessary words, I will simply state, I will leave firefox if you do not eliminate this problem:

firefox eats up all the RAM on my Mac. It is none of your business whether I open 1 tab or 10 tabs, give me the ability to limit the memory used by firefox, otherwise it eats up all the computer's memory.

Hi, after update 137.0.1 (64-bit) using Firefox with latest Gecko driver 0.36.0 in Python Selenium stalls and fails to initiate drivers without returning initiation errors every second launch, previously this stall without returning initiation errors would happen every ~25th launch. Also when it does successfully launches previously 9 instances used to use about 95% of my 8 GB RAM, now 6 instances use 100% RAM. Nothing else in my system changed besides Firefox update.

Hi Community,

I am writing as recently I noticed that extreme amount of data was written on my system SSD. Here we are talking about 100-200GB of data written daily. In resource monitor I found that Firefox is writing this amount of data in its Profiles folder, but only when Facebook's main page is open. I also noticed that when only the Messenger part is open the problem goes away. Currently I symlinked the Profiles folder onto one of my HDDs so the data is being written there, however I would like to know if anyone experienced the same issue and what could be the solution for this. I completely reinstalled Firefox, my installed extensions are Adblock Plus, Enhancer for youtube and Facebook Container.

I have two Firefox tabs open on my browser. Task manager shows 35 tabs using 897 MB of memory. How do I make this stop? And why are so many tabs running? I have cleared cache, cookies, etc.

There is a similar (but not identical) topic on Mozilla Connect , and I posted there. But I did not get a response. So I am re-posting on this new topic on Mozilla Support. I have a similar problem to what was discussed on Connect. I am using Firefox 133.0.3 on Windows 10 Professional. After Firefox has been running for a while, I get a message from Windows 10 that the free space on my C:drive is low. I did a directory listing on my C-drive before and after Exiting Firefox; I saw no large files disappearing. Then I decided to do "dir c:\ /ah" to see hidden files. What I saw was that pagefile.sys decreased in size from 29,925,748,736 to 16,270,770,176. This was a decrease of 13.7 Gb. Is this normal? I have lots of windows and tabs open in Firefox. Thanks.

I’ve noticed that Firefox consumes a lot of memory, especially when I have multiple tabs open. Sometimes, it slows down my entire system, and Task Manager shows Firefox using over 1GB of RAM even with just a few tabs. Other browsers like Chrome or Edge seem to handle memory better with the same number of tabs.

I’ve tried restarting Firefox, closing unused tabs, and disabling a few extensions, but the problem keeps coming back. I even checked techsquest.com for tips, but I’m still struggling. Are there specific settings, hidden features, or optimizations I can apply to reduce Firefox’s memory usage without sacrificing performance?

Here’s what I’ve already checked:

Firefox is updated to the latest version.

No unusual extensions running (just uBlock Origin and Dark Reader).

Hardware acceleration is enabled.

Any help would be appreciated—thanks in advance!

Lately, I’ve noticed Firefox consuming more RAM, especially with multiple tabs open. Is this a common issue in recent updates? What are some tips to optimize Firefox performance on lower-end PCs? Would love to hear your experiences!

Please assist or advise why Firefox seems to be slowing down my system by memory usage. I have a handful (6) of tabs open on 1 browser session and my system started slowing down so I checked my task manager and it shows that I have more than a dozen of Firefox instances open chewing up almost 90% of my memory.

Please assist or advise me on how to tweak my browser to perform better, and not to show ghost instances