Firefox Community Forum

FIREFOX ... MMMMMMMMMMMMMMMMOOOOOOOOOOOOOOOOORRRRRRRRREEEEEEEEEEE THAN 16 GIGABYTES WITH ONLY 4 TABS OPENED. AND OF COURSE .... BROWSER FREEZES, NEED TO KILL FIREFOX TO STAR WORKING AGAIN ....

WHAT ARE YOU SMOKING THESE DAYS?

I've just opened one simple Web site (in addition to Mozilla), and already CPU usage sits at about 20%! Please refer to my recent posts here at "Why is Firefox Suddenly Taking Over my CPU?" for the problem description. I'm re-posting simply in hopes that I can "send data" on this one from outside my sandbox. Regards -- jclarkw

Today Firefox has suddenly started using ~20% of my CPU capacity, causing my cooling fan to run high most of the time. Since I had been running Firefox v.149.latest, I tried updating to v.150.0, but that made no difference.

It's not Firefox by itself (only Task Manager open) but whenever I open another tab with almost any website (including this one) that CPU usage spikes. What gives?!

Details: Running under Windows 10 Pro (yes, I have installed the ESU package, good until thi8s fall) on a Lenovo P1 Gen 2. Currently running Firefox inside a Sandboxie Pro v1.17.4 sandbox.

Please Help! -- jclarkw

Been using Firefox for over a decade. But lately is has become so slow now. Often freezes up if more than two tabs are open or a website is in any way very complex. What settings and issues should I check? What has changed? I can run the same sites on Brave and Edge browsers with no issues or not nearly as slow and bogged down.

Hello, I'm on Firefox Nightly 152.0a1 running on a freshly installed new Windows 11 version. I've used Firefox exclusively for my whole life and everything has always been smooth until a few days ago. Firefox started (and continues) to freeze for a second or two pretty regularly, each time I use the search bar for example, open a new tab, while a page is loading (which is very slow at the moment) but also scrolling on a page for example. During the freezes, the temperature of my CPU also increase by approximately 20°C. CPU usage in task manager shows that it is quite high, 10x higher than Edge that I opened for comparison only : https://i.imgur.com/enuMMZl.png.

I have sought the internet for advice but nothing changed this behaviour. I updated my computer through Windows Update, my drivers through Driver Booster, I disabled hardware acceleration on Firefox, I removes all AI components with zoicware/RemoveWindowsAI on GitHub, I changed dom.ipc.processPriorityManager.backgroundUsesEcoQoS on about:config to false but nothing cured the problems.

I'm out of solutions and I don't know if I should be waiting for another Nightly build (usually there's about 1-2 a day but 152.0a1 is sticking since a few days and there isn't any update available since, seemingly), if there's others energy economy parameters I could play with on Windows 11 that I don't know about or if something else is in the way. Any help very appreciated, thanks!

I recently upgraded from Ubuntu 24.04 to 26.04, using Mate Desktop and Compiz compositor. I am using Firefox from the Mozilla Team PPA, currently 150.0.1. I am running custom kernel built from upstream source, currently 6.18.25. Hardware is a home brew CoffeeLake machine, i7-9700k, 64G of RAM, 2TB WD Black SSD and many TB's of spinning rust, graphics is Intel ARC B50 Pro, ASUS XONAR SE 5.1 Channel 192kHz/24-bit Hi-Res 116dB SNR PCIe Gaming Sound Card. Prior to upgrading Firefox was not 100% occasionally tabs would wedge, now if I get two hours I'm doing good, I've tried disabling extensions and plugins no help. Tried with and without hardware decoding, worse without but bad no matter. Any suggestions how to get stability back?

This new issue is puzzling:

Normally, on MacOS, when you minimize an app that's currently running and occupying the desktop, say by clicking the orange button at top left or by clicking another app, its menu would disappear from the top toolbar and other apps could then be invoked. Clicking that app icon again would restore it to the screen and its menu would again be on the top toolbar.

But Firefox has stopped allowing that behavior: Now, when I try to minimize Firefox, while its screen minimizes (revealing the desktop underneath), its menu remains on the top toolbar. It is as if Firefox refuses to let go of the controls. So, while you can see the other icons on the desktop - say file folders - they are unresponsive to clicks and do not open when you click them, as if Firefox is not letting you access File Manager.

Furthermore, you can still access these desktop file folders, but only by opening the finder using the bottom toolbar menu, not by clicking the file icons directly.

For what it's worth, all menus are still responsive (bottom toolbar, top toolbar, apple menu), just nothing that's on the desktop responds when Firefox is still running, despite being minimized.

After latest update Firefox Developer Edition 151.0 Beta 4 I noticed much slower website loading while using few containers at the same time and overall more lag. Before the update everything was great and smooth I hope it's gonna get fixed soon.

after working in firefox for a while and using a number of windows and the I close firefox with multiple windows open in my session. if i open it again and keep doing this for a while and then have closed firefox, eventually I can no longer open a firefox window and get a message the I have too many windows opn and can't open more till i close the open windows. i hover over the firefox app and all the previously closed windows are stacked up. why didn;t they close when i exited my firefox sessions. why are they still there and clogging up the system?

My Dell Precision Laptop from 2019 runs a frequently updated Ubuntu 24.04. About one or two weeks ago, after one of the latest Firefox updates, i noticed that video streaming produces rectangular flickering in rapid sweeps. ( Also fast scrolling large text websites produces similar flickering, I think I would have noticed it before...) . If you detected it once, you see it always again... :-( First I fiddled around with the nvidia settings because the driver was also recently updated, without much success. Playing locally stored videos, e.g. with VLC media player, still works fine, so the nvidia driver is not the problem i think. Yesterday I installed Chromium and the video performance is fine! As good as with firefox some weeks ago! So it must be one of the latest updates, that causes the problem. Generally I like firefox more than chromium. I like the control you have, e.g. via Add ons.. So I hope that the firefox performance will increase again... Thank you for firefox! Florian Mengedoht

Arch Linux Wayland FF v150 from Arch repos

When right clicking the context menu appears, but sometimes in odd places, and the disappears, so you can't select anything.

Same is true selecting the Help submenu from the Hamburger menu.

Restarting the browser fixes it for a few minutes, then same problem comes back.

Other people also reporting the same thing - also Linux Wayland: https://www.reddit.com/r/firefox/comments/1suounc/comment/oi7jk9u/

Even with just 1 tab open, Firefox is killing my laptop battery.

Win 11 PC laptop.

In background, it is using 40% to 50% of the laptop battery. I need much better performance from it. I have already turned off any settings I can find regarding Firefox's background functions. When I quit Firefox I want it completely off.

How can I do that?

I often keep many tabs open for research, and Firefox memory usage grows significantly over time. Are there practical settings or habits that help manage memory without sacrificing usability?

Hi Mozilla Can you improve firefox 115 in next update because this browser is slow and need to improvements in performance, i'm using windows 8.1 and i'm can't upgrade to windows 10

Hi,

I’ve recently noticed that after a Firefox update, the browser has become very slow and unresponsive whenever I open multiple tabs, around 5–10. Before this update, I could open many tabs without any noticeable lag.

Now, new tabs take a long time to load, scrolling within open tabs feels choppy, and sometimes Firefox freezes for a few seconds before responding again.

I’ve already tried restarting Firefox, disabling extensions one by one, and clearing the cache, but none of these steps have improved the performance. I’m using Windows 10 and the latest version of Firefox.

Could anyone suggest what settings or troubleshooting steps I can try to fix this slowdown?

suse linux 15.6 firefox 140.9.0esr (64-bit)

An aggressive website can cause "isolated web co" processes to be started. When they hog all processors and memory, the computer besomes unresponsive. Keyboard and mouse freezes up.

Is there a way to limit firefox processes to n-1 processors, leaving 1 processor available for me to kill it ?