I-Firefox Community Forum

In 2024-25 Microsoft Edge gained the ability to limit the usage of physical RAM that the processes uses. Once that limit is reached tabs are put to sleep or are unloaded. So a user of Microsoft Edge could restrict the memory usage to say 1GB or 2GB or 3GB and so on till the maximum available physical RAM.

Does Firefox have such an ability? Is there some flag or settings in about:config that can be enabled for a similar feature to be used? Does Firefox have ability to put tabs to sleep once SWAP is started to be used? Is there some flag or settings in about:config that can be enabled for a similar feature to be used?

If none of one of the above is not available with Firefox then will Firefox add this feature as part of the browser in the future?

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.

I have a two monitor setup. Since I installed the new AMD driver (26.1.1), sometimes when I play a game on my main monitor, and watch stream on Twitch in Firefox on my second monitor, it can cause the PC to freeze completely. I hear the sound, but the image is stuck.

I tried to disable the hardware acceleration in Firefox, and it seemed like a good solution. But because of that (which is its function), sites became laggy.

Is this a Firefox, or an AMD issue? Or Windows (I'm on Windows 11 25H2)? I will try to install an older AMD driver, but honestly streams had became laggy before the driver update for me.

On updating to linux mint 22.3 - cannot type anything in firefox in address box, search and primary password or anywhere else within firefox - have uninstalled & reinstalled but nothing happens

I am a Cacti developer and we are considering switching from FontAwesome Web Fonts to Tabler Web Fonts. However, on Firefox for Windows only, we are having a major slowdown when using the Tabler SVG based webfonts. The page load is first stalled by Firefox apparently loading all the Web Fonts, which would appear normal with any browser (though exceedingly slow on Firefox for some reason).

However, once the page is loaded, when going off tab to another browser tab, and then back to the Firefox tab that includes the Tabler webfonts, there is a 3 second delay before the tab switches. When we enable the performance analyzer, we find that the delay is almost 100% Reflow of the page, even though the page is static as this point (no changes) from the last time it was activated.

We do not have this issue on Firefox for Linux, MS Edge or any other Chromium browser, only Firefox on Windows. I'm using the latest version 134. Should I be opening a bug?

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

I've been using Fire Fox for decades, but lately it is so slow, I thought there was something wrong with my Windows 7 ultimate. I've done full Windows reboot, to no avail. Then I see the internet t hat FireFox is starting to implement AI. I thought that may be the issue, but after looking into it, looks like that isn't an option with my old Win 7 OS. So if that isn't the problem, how can I find out what is bogging Fire Fox down? I keep a watch on my CPU usage, and the usage is going nearly to 100%, when it used to barely go over 10%. When I check the actual CPU usage, it shows as many as 15 or more items tied to Fire Fox.

Is this all a result of continued use of Win 7? I'm planning to move to Linux, but that will take me some serious time and effort. Gerald

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.

A couple days ago, some weird issues have started:

• All my bookmarks are gone
• Any of the buttons in the UI that open a smaller UI do not work (such as the 3 bar menu)
• Similarly, right clicking to open a menu (such as "Save Image") also does not work
• Any dropdown menus in websites seem to also not work. For example, in this very support page, I could not select an option in the "Which topic best describes your question?".

I can't restart and troubleshoot Firefox since I can't access the 3 bar menu.

I run a drafting site where we share shop drawings for contractors and architects: https://usadraftsman.com

Whenever I open these drawing preview pages in Firefox, the browser gets slow or sometimes becomes unresponsive. The same pages load completely fine in Chrome, so I’m trying to understand what might be causing this only in Firefox.

Most of the previews are large drawings or viewer embeds, so maybe Firefox is struggling with rendering them. I tried clearing cache and turning off extensions, but the issue still comes back.

If anyone has dealt with similar heavy graphics or rendering issues in Firefox, what should I check or adjust? Any suggestions would be appreciated.

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.

I have been using Firefox for many, many years. As of late I find it is constantly slowing or freezing and when I check with taskmanager I find Firefox has opened and is running as many as 85 processes. I have tried the recommended methods of limiting it...but the performance options do not provide the ability to limit processes as set out in the instructions....and changing the browser.tabs.remote.autostart to false also did not work. If I can't fix this, I will have to stop using Firefox. I am using version 144.0

Hi, I'm on Firefox 147.0.3 and windows 11 business 25H2 (26200.7623), with two displays. For the past few weeks: - firefox stays on top - alt-tab to other window on that screen doesn't work, other app is not displayed over firefox - clicking on other app icon in task bar doesn't bring it to foreground/top - even other firefox window (like new private window) is opened in background - the only way around is to minimize firefox - without firefox opened, everything works normally It is really disturbing my flow / ways of interacting with apps / habit of using keyboard to move between apps.

Is it a bug, or is it a matter of some settings? I've seen similar quesiton from 9 years ago https://support.mozilla.org/en-US/questions/1140245 but there is no setting of the same name now?

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.

При заходе на сайте ya.ru и если на нём имеется строка с видео или поиск с алисой, то начинаются сильные фризы. Это ошибка именно в firefox 142, проверенно.

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.

I have a problem with 'efficiency mode' in Windows 11. Windows 11 forcefully puts many of Firefox's tasks into efficiency mode marked by green leaves within task manager in processes tab. It doesn't seem to do this to anything else except Steam Client WebHelper. My Laptop is always in max performance mode in all possible settings as it is always plugged in (this does not influence efficiency mode). It slows down performance making things take longer to load and might even break them. If you try to enable efficiency mode on a task it even warns you of this: 'Efficiency mode will lower process priority and improve power efficiency but may cause instability for certain processes. Do you want to continue?' There is no way to permanently disable it. Currently out of 19 tasks 8 are in efficiency after I woke up my laptop from sleep (I have 5 tabs open). Only way to stop it is to manually disable each one by one (right click on each task and disable efficiency mode). But Windows 11 will turn them back on automatically usually within a few seconds (it seems to depend on opening new tabs, reloading them or waking up the PC from sleep mode). From looking it up online there seems to be a way to disable it in browser on Edge and Chrome but that might be something else (I do not use the so I'm not sure). There was a solution for Chrome but it doesn't work on Firefox.

Is there any way this can be disabled permanently through Firefox or Windows 11?

Since a month or so, Firefox browser freezes when playing youtube videos. Simply closing the app and restarting won't do the trick, I am forced to open the WIN Task Manager and manually "end task" before I can watch youtube videos again ... until an hour later, or lucky a day later, the same drama unfolds. I run the newest version of each, Firefox and Windows 11. No new extensions or plugins have been added recently. What is to do here? I'm since Netscape on this route and would hate to switch to another browser... :-) Thanks in advance!