كل المنتجات Community Forum

I use Brave, Firefox, Firefox Developer Edition and Thunderbird. Brave: 600mb Firefox Dev: 600mb Thunderbird: 200mb Firefox: 800mb Why is Firefox using too much memory? Especially as I am running Firefox Dev as a direct comparison. I don't have any plugins on Firefox. Firefox Dev has uBlock Origin alone. Brave has a few plugins.

Recently I've had this issue (on reddit) where after I expand a video in the feed, and start scrolling, all the visuals freeze.

I know it's only the visuals, because I can still interact with the website (usually unexpand the video, or pause it) with the image still frozen and audio still playing.

I can fix it by tabbing firefox down, and then up again. While researching I found the profiler, and finally managed to capture the moment it happened.

I'm no stranger to technical stuff but it's a loooot of data to process, I did a "clean" profile recording as well where I did the same action and where it didn't freeze, and I can't really make heads or tails out of what the issue is.

The recording managed to capture the phenomenon and I only clicked twice during that period, to expand two reddit expando videos, the second one is what caused the issue when scrolling. The only thing I see is a spike in memory usage

Not sure if I can (or should) upload the profile recording here or what, but it's been bugging me a lot.

It's pretty tricky to replicate because it seems to be random when and what triggers it, even expanding the same videos doesn't replicate it. Sometimes I go days without it happening, sometimes it happens 6 times in a single session.

I've added some screenshots of various views of the profiler/stack data.

I have an Nvidia RTX 5070ti GPU, hardware acceleration is on, AMD Ryzen 7 9800X3D processor.

I think I might have enabled some rendering settings in about:config, maybe it's related to that but I don't remember exactly what.

Maybe it's due to some windows "game optimisation" or the GPU and CPU-GPU fighting?

I have no problems watching videos while playing games or anything though.

Hi Everyone,

I’m Harmandeep Singh Kandhari from India, A Health and Wellness Motivator and Now, Recently, my Mozilla Firefox browser has started using much more memory than usual, and multiple tabs cause noticeable slowdowns. I haven’t installed many new extensions. What steps can I take to identify the cause and optimize Firefox performance without resetting my entire browser profile? 🦊💻

Thanks, Harmandeep Singh Kandhari

When starting firefox on android and pc, it will take a long time (in relation to other browsers) to display any webpage I gave set as default. Even Google search takes a long time to display. It's not the speed at which te page is loaded, is the time between the start of firefox and any action. Even the adresbar stays empty during this time as if firefox is stalled. I've installed a fresh Firefox instalation and removed all add-ons (recommended or not) and Firefox still start ms slow. On my pc I can see the cpu and ssd speeds and for a second of 15, while Firefox loads, the cpu usage seems normal (6 core with no other program using all cpu cores or without any cores above 15%) and the ssd (NVMe) isn't even above 1%.

And with the android version, switching temporary to another program (to look something up) causes the webpage te become blank or black and requires an refresh (for instance, if I switch to another app, this page will be blank, or back and all this text wil be gone because I have to reload thus page) it only affects the web pages, not Firefox itself (the menu an adresbar wil stil display correct) and the refresh, no matter how fast it loads after the initial firefox start, Will be as slow as if firefox is (again) starting.

I do not want to switch to another browser. Even with these annoying problems, but if these problems can be removed, I will enjoy firefox even more!

For the past 15-16 days, Firefox has been consuming extremely high memory.

The problem: - When Firefox first opens, it starts normally at around 300-400 MB - But after using it for about 1 hour, a single Firefox window grows to 1-2 GB of RAM - This keeps increasing the longer I use it (memory leak behavior) - Currently Firefox (41 processes) is using over 5,131 MB total memory on my system it's normal but after 1 hour a single firefox window grows to 1-2 GB of RAM

What I have tried: - The issue happens consistently every day for the past 15-16 days - Other browsers like Chrome and Chromium use much less memory in comparison

System info: - OS: Windows 11 - Firefox version: latest version 148.0.0.0

Please help me fix this memory leak issue. It is making my system very slow.

Whatever changes were implemented around start of March 2026 have made bookmarks almost completely unusable for me on Firefox Android. I have a set of bookmarks shared between my phone and my synced desktops, and they're all in folders within the Bookmarks Menu folder under bookmarks.

Since the change I mentioned, when I go to edit the folder a mobile webpage bookmark is in, it shows me the bookmark details, and when I click to change the folder, it shows me the Bookmarks Menu folder and the Bookmarks Toolbar folder and one other folder. Normally at this point I would expand the Bookmarks menu folder to see the subfolders and select one. But after I click on Bookmarks Menu it takes many minutes to expand (I don't know how long; I needed to do other things so I went away and came back to it) and many minutes to expand any lower layers in the hierarchy.

This is completely unacceptable. If you offer a bookmarks service, it should be possible to expand the folders of bookmarks within 3 seconds. It is completely impractical for it to take multiple minutes to expand each folder level, especially since Firefox always collapses all the folders before the next time I try to edit a bookmark folder.

Please fix this ASAP!!

Initually I was having issues where I couldn't get the print menu to load up (forever stuck trying to load the preview), however since then it has progressed to downloads refusing to download and the hamburger menu in the menu bar doesn't react when left clicked at all.

In Firefox's Task Manager, how do I know which tab is using which subframe(s) process?

For example, let's say I open Firefox and with only one single tab open, I open the following web page: https://audioplugin.deals/product/best-of-zampler-collection/

That page apparently includes content from several third-party websites because when I open it, Firefox's Task Manger shows processes for the following:

https://audioplugin.deals https://cloudflare.com https://google.com https://hcaptcha.com https://soundcloud.com https://stripe.com https://stripe.network https://stripecdn.com

The process for "https://audioplugin.deals" is the only process with a tab. All of the other processes are subframe(s) only, with no mention of which tab is using them.

With only one tab open, I intuitively know that all of these processes must be used by that one tab. But like most people, I browse using multiple tabs, and once you open multiple tabs, it becomes (as far as I can tell) impossible to determine which subframe(s) process is used by which tab. This makes it impossible to determine which tab is behaving improperly or erratically when there are issues (for example, when one of those subframe(s) processes is consuming an unreasonably large amount of memory or CPU cycles).

I am just an average end user and want to alert you to my problems and would love a solution. I am sorry that I don't have the kind of specificity in the details which might help (I am too busy doing other things and when firefox becomes too much of a pain, I generally close it and switch to another browser). I am providing my general observations. On my updated windows 10 64 bit system, firefox v148 seems to have made the browser unusable for me. Other browsers do not suffer similarly (Chrome, Edge, Opera, duckduckgo). I have had these types of issues with Firefox in the past, but they resolved with prior updates. I am at the point of switching to another browser - I hate the thought of it, but Chrome seems to be the most stable and functional. Symptoms:

• Firefox browser and the computer gradually become slower as firefox starts hogging cpu and memory and starts using a lot of power
• extensions stop working - eg, Keeper extension stops filling fields or fills incorrectly, Malwarebytes extension seems less responsive, running background sounds makes things even worse (https://www.mynoise.net/) and web pages with continuous updates (eg, map.purpleair.com) stop working altogether
• other pages stop loading, load with errors ('bad connection') or load very slowly, especially, but not always, those with more security, eg, my bank or retirement funds sites.
• after i close Firefox and start fresh, symptoms resolve, then rinse and repeat.

The previous version worked great and seemed to solve similar issues I have had with earlier releases. I assume the last stable release for me was one of the 147 versions. but when things are going well (which is most of the time), I'm not watching closely, or at all.