Firefox Community Forum

Ubuntu - I use the SNAP version of Firefox - I generally have lots of tabs open but only use 5 or so of them and it's generally fine.... but when I am closing Firefox, it USES like 100% of the CPU and ALL of the RAM and ALL of the SWAP memory when closing.

This locks up the computer.

Sometimes it doesn't quite go all the way but I can watch it all happen in real time, using Task Manager - and that shows a solidwall of all resources occouring, when the close Firefox is run.

I am told by research via ChatGPT that this is a very real problem with the SNAP version and it's best to change to the Debian version, copy all the bookmarks etc., across and then uninstall the SNAP version.

It's rather disconcerting to have Linux crash because of this one app locking it up and frequently.

Chat GPT:

Is there a problem with Firefox Snap Version closing and using all the resources while doing so, which results in locking up the computer?

You're definitely not imagining it—there have been reports of Firefox's Snap version consuming excessive system resources (CPU, memory) and even causing lockups or hangs, particularly during closure. Here's what’s going on and how to mitigate it:

What’s Happening with Firefox Snap?

2. Browser Hangs or Locks the System on Close

On Linux (especially Ubuntu), users have reported that closing Firefox can lead to it hanging in memory, sometimes unresponsive and still consuming resources.
Super User
Ask Ubuntu
A stark example from Reddit illustrates the severity:
“About 50% of the time I open Firefox, it'll reach 100% CPU usage in about 30 seconds… PC completely unusable unless I shutdown.”
Reddit

3. Known Wayland Sway Bug

On Wayland/Sway setups, reloading Sway while Firefox is open can trigger intense logging, causing high CPU use and an enormous syslog.
Fix: Set MOZ_DISABLE_WAYLAND_PROXY=1, or upgrade to FF 125 where the issue is addressed.
Reddit+1

Alternative Approach

Many users, particularly on Ubuntu, opt out of Snap completely in favor of the .deb package or PPA builds. These alternatives often avoid these specific issues. Ask Ubuntu Reddit

Thoughts? Solutions?

Thanks in advance.

Windows 11. I have my taskbar behaviour set to ‘Automatically hide the Taskbar’ So usually the Taskbar is not displayed, but when I move my cursor to the bottom of the screen it reappears. With Firefox I cannot make the Taskbar reappear.

After every update, Firefox starts to a blank screen and will not start loading the webpage url put in for over twenty minutes to a half hour. During this time other browsers on my Win 10 PC load immediately so it is not a network issue. It is Firefox. When I see that an update is pending I hesitate to do the update because I know I will lose the use of Firefox until it is ready to respond. It just hangs with "loading X.com" showing at the bottom left of the blank screen. I have been using Firefox for a long time and in the past year or longer it has become very unreliable. There are also instances where without an update it will do this and the only way I can get it to work is to clear the cache and the history through settings. What is going on with Firefox! (And lately there is an update every couple fo days!

I booted the computer this AM and firefox is acting up. I can go to my email accounts (2), but I can't open an email. Both act like this. They will open with MS Edge and all other functions seem to work on the computer except for firefox.

I tried searching for a solution using duckduckgo and google, many of the links wouldn't open and some that did, just loaded re-loaded, but never finished. Pulldown menus, where they ask a question and click to see the anwer, don't work. They are frozen. Can see the cursor highlight the menus, however it will not allow any interaction with them.

I restarted the computer, there was an update, and I had it update. No change with firefox. I reinstalled firefox. No change. For the moment, I'm out of ideas. Anyone have any thoguhts about this, please help. Thanks in advance. Ken

Hello For some reason most of the buttons in my toolbar have stopped working. When I first open Firefox they all work, then when I enter websites they stop working. The 'home' button still seems to work, but almost all others (such as the 'back' button etc) can't be selected. This is very frustrating. To note, I am not tech savvy at all.

Thank you in advance for your help.

Andrew

Using desktop 141.0, noticed issue of the hand pointer either not appearing, or appearing for less than a second and disappearing when hovering over buttons/urls/etc elements. Sometimes it stops being buggy for a minute or so and then goes back. I can't figure out the exact cause for this, but maybe going outside of the window of the browser ? Consistent in the safe mode, on different websites. See the gif for the visual

Whenever I start my machine, without opening Firefox, Ctrl-Shift-I works (For inverting selections in certain programs, for example).

However, once I open Firefox, these 3 keys no longer work when used together (but work in any other combo).

This persists even when I close Firefox, or kill it in Task manager.

Any ideas?

Cheers

Just a note that I had a lot of probem with the firefox not opening when a link is being clicked. It would open in background but not come to focus.

External hyperlinks do not open in Firefox window.

I found that focusmanager.testmode was the cuplrit, after a lot of hard work.

Добрый день! Обратил внимание, что с последним обновлением. у меня стала виснуть браузерная строка полностью и я не могу зайти в настройка. Уже было несколько раз так и мне помогает только полный перезапуск браузера.

Я могу прислать видео, как это выглядит.

Прошу помочь решить эту проблему. Спасибо

It seems that since the Version 141.0 update, initial startup of FF seems to take ve-e-e-ery long (approx 3-4 minutes).

The startup time/lag seems almost the same as it takes to restart after an update.

Anyone else experience this also? Thanks.

I downloaded Firefox not too long ago to combat the fact the Microsoft Edge wasn't working correctly, but ever since I downloaded Firefox it's been making my computer run really slow on the browser. Things are often slow like scrolling up on and down pages websites like Pinterest, and the text when typing on Google docs takes a moment to show up after I've typed it and not instantly, for example.

I checked my computer's task manager because I recently cleaned the laptop, thinking that something else was causing it to be slow, but it isn't. I don't have many processes open on the computer mainly mandatory things and my browser, since I use my laptop mainly for school work, music, or writing. Firefox opens multiple processes, the highest being 21 at one time, and takes up most of the memory on the laptop. Is this normal? Because it takes 1,094.0 MB and keeps my laptop's memory at 90-91%. If it isn't normal, how can I reduce this as well as the lag on my laptop when Firefox is open?

I attached a photo as well.

Hello team,

I tried searching for a solution for the problem I'm about to describe but unfortunately I wasn't able to move forward.

I am running Firefox 141.0 version on my Macbook M4 Pro. The refresh rate of the display is set to 120Hz, but I the scrolling and interaction in the browser feels like it's on standard 60Hz refresh rate. When I compare it to Safari/Chrome it's not as fluent as it should be.

Am I missing an existing option that could be changed or is it something available at the moment?

Thank you, Arsen

I'm using Firefox 141.0 on OpenSuse Tumbleweed with KDE and Wayland. I'm using Firefox with two profiles: work and personal - which is (usually) awesome, until suddenly it's not.

Then, one or both profiles seem to become corrupted, and closing firefox, opening it, choosing either profile just hangs forever. My old tabs show up, but clicking on any tab, for any site, just hangs forever, and no page is ever loaded. Sometimes restarting helps, but sometimes not. Sometimes restarting 2 or 3 times and then suddenly it will work. But normally, I have to just delete all my profiles, and re-create them. Fortunately everything is synced with Firefox sync. Then everything will work wonderfully for a bit - although I have to re-login to everything.  :-(

Any ideas? This is a huge pain and productivity killer. I really love firefox, but this sucks.

About two weeks ago, Firefox started randomly hanging and would stop responding. It wouldn't let me close the program and I always have to restart my system to resolve the problem. Sometimes it only takes a few minutes after restart before it hangs, other times it will be fine for hours.

I've tried multiple solutions I've found online, carefully following instructions: clearing cookies and cache, disabling all extensions, refreshing firefox, creating a new profile, deleting specific files within the Profiles folder, etc.

I've yet to make it more than four hours without the program hanging.

Any assistance or suggestions are greatly appreciated.

This problem just began today on my Win 11 laptop. Firefox is current - 139.0.4. Win 11 is current. No new software has been installed. Firefox hangs up and will not move. Task manager shows FF is consuming more than 90% of my 16GB memory. I must end the FF task to get up and running again.

Gmail is slower than frozen molasses, it is taking 15 to 20 seconds to respond to mouse clicks and typing as well as scrolling, it takes me more than half an hour to do what should take a few minutes, if this is not fixed soon that will be the end of Firefox for me, I will use Opera instead.

Hello. From time to time, a problem with tabs and the settings button in the Mozilla browser occurs. The tab close buttons and the settings button stop responding, are not pressed, tabs have to be closed manually using the right mouse button. Everything starts working after restarting the browser, but again after some time everything stops working again. This happened on version 138 and I observe it on 139. Installed Operating System: Garuda Linux KDE Plasma Version: 6.3.5 KDE Frameworks Version: 6.14.0 Qt Version: 6.9.0 Kernel Version: 6.14.9-zen1-1-zen (64-bit) Graphics Platform: Wayland