Firefox Community Forum

My Macbook Air (M1, 2020) has be moving slowly recently. I wondered if how I'm using Firefox could be contributing. I typically have two Firefox browser windows open, with 5 or 6 tab groups each with several tabs.

In addition and more specifically, I'm wondering if closing (collapsing) a tab group means those tabs won't be contributing to my computer's CPU load. Thank you.

Hi. My Macbook Air (M1, 2020) has been performing slowly in recent days. I'm not playing video games or watching videos, just mostly working on many tabs in Firefox (157.0.1). I looked in my Mac's Activity Monitor, which shows that Firefox GPU Helper is using about 5.75 GB of memory. The next few highest users say "Firefox Isolated Web Content." Could any of these be what is slowing my Mac down? I'll attach a screenshot of my Activity Monitor. I also clicked "Share Data" below. I would say that my Macbook is working at a fine speed at the moment, so perhaps the screenshot and data are not so helpful. Let me know if I can add something later in a reply, when my Mac is moving slowly, that would be helpful. Thanks.

Firefox freezes some seconds or some minute after I open the program, I end task and wait to reopen the program, opening up the program it continues to freeze. I've reset firefox multiple times, cleared cache & webdata, completly uninstalled FF and reinstalled it, doesn't solve it. Starting firefox in troubleshooting mode also freezes and hangs. After end tasking firefox multiple times it eventually stops freezing but during the next day when I open the browser the issue returns, The same goes after I reinstalled it after uninstalling it, works for the rest of the day but the next day the issue returns. Background: I switched from chrome to Firefox some months ago and imported webdata from chrome to FF.

This morning, I can no longer download (Save) files to my computer, nor check/change settings in Firefox. Tried all troubleshooting steps to no avail.

If I delete and reinstall Firefox, will I lose all my Bookmarks, etc.? Running version 157.0 (aarch64).

Appreciate any help!

Hi guys - I am running Firefox 157.0 (aarch64) on a Macmini M2 pro with 32GB RAM .

I am regularly receiving messages that my default browser, Firefox, is the largest consumer of that RAM. This is what I received this morning shortly before my system shut itself down. I did have many files open but noticed that Firefox is consuming 33GB of my RAM. Is this normal?

Original FF user here so not a newbie. Run all FF updates on a regular basis. Currently on a MacBk Air circa 2020 running Sonoma 14.7.7 I browse twitter on a regular basis. I run various ad blockers: ABP, Adblocker Ultimate & Privacy Badger. Last month or so I've needed to make some adjustments as maybe the X platform has instituted workarounds or something but suddenly I was seeing ads that looked like someone's post, very deceptive. At one point it was necessary to disable Privacy Badger on twitter/X as there was an interference w what I was seeing. That wasn't that long ago, maybe 2-3 wks? Consequently if I saw an ad I needed to do a "block element" thru Adblocker Ultimate & while it was a bit of a bother that was all fine and good no problem. Again, this was all recent. Tonite was different. An ad appeared and somewhere something got entangled and I had to disable the Adblocker Ultimate. I sent them an email to see what's up. Then I had to disable that on twitter so ads appeared. Next I tried to enable ABP again on twitter to see if maybe since I'd disabled it a couple of wks prior maybe it had been updated and would work ok. This is when things really started to go downhill. It worked but too well - was disabling images from news reports and/or someone's posted video. THEN I noticed my cpu was running a bit loud. I tried to disable/test the ad blockers but my cpu was getting louder so I shut down the twitter website altogether.

That didn't help. I checked the Utility monitor and saw my activity monitor climbing as I heard the fan running louder. SO bizarre! I shut down FF altogether and this calmed down the CPU. Next I opened just a general news site - Al Jazeera - to see what would happen. Within about 2-3 mins the CPU started speeding up again. I closed AlJazeera, and just sat there for a few moments and my cpu calmed down. Opened it again same thing. Began speeding up. That's when I came here to file a report//ask qs because this just doesn't ever happen - literally ever. It is not unusual for me to have both a browser page open w 2-3 windows along w a private window open - maybe mltiple windows there - and NO cpu noise going on. Once more I shut down FF completely before reopening a new window. IF I start browsing a news site - like Al Jazeera, it begins running hot again. Twitter, same thing and now my ad blockers seem to be messed up//not working as well. Right now as I type this I have ABP & AdBlocker Ultimate both highlighted as active; Privacy Badger is showing enabled but no activity, Twitter Video Downloader is just sitting there as is typical unless I need it (it's to download videos off of Twitter, works very well too.) That's all I have for add-ons. Right now in just this window everything is calm and quiet. IF I open a news site tho, or social media, anything w a bit of activity on it everything starts humming louder and louder. I just opened FB for a few moments to see if that creates issues and yes it does w/i maybe 2-3 mins of activity. Also: FF Privacy & Security Settings are on Standard. Not sure what else I can provide but please feel free to ask. I may have left something out. I'm hearing the cpu heat up again so getting ready to just shut things down for the night. Thanks to all who helped build FF - really - and thanks to whoever can help resolve whatever's going on now.

Hello there,

I realized that quite often when I restart Firefox (Developper Edition) and restore my previous session (latest occurence with 46 tabs), the window becomes invisible. It still exists, and I can even see it in the Window menu list pointing to my latest tab but it's nowhere on screen. I can add/navigate through/select/remove tabs using the keyboard, I can see them listed on screen when I Ctrl-Tab but the whole window remains invisible.

It'd be great if someone could help me out.

Best regards,

Emmanuel

starting about a month ago, my Firefox browser has become very slow. Sometimes now when I click a link (this happens about every 4-5 links) the spinning wheel of death appears and the browser doesn't respond. I have to force-quit

Since version 154, my 2017 Macbook Air running MacOS Monterey causes my fans to be always on. The battery preferences says "Using significant amount energy." I've turned off all AI features.

First post. Not really a question.

I noticed last week that some pages didn't load, and Activity monitor showing Firefox app using 170-180% which I know is way too high. Forgot to check memory usage.

I rolled back from 154 to 153 by restoring it from backup, and same with the Firefox folder in ~lib/appsupp/, relaunched Firefox and cpu was back to 2-4% cpu with a couple of windows and tabs. I've turned off auto-updates.

On my system, something is wrong with v154.

Mac Mini M4 Pro 12-core 24/512, macOS 15.7.5.

Hi folks My configuration: MacOS Tahoe FF 15.4.0 When I relaunched FF after restarting the Mac, in the Windows menu all the pages from the previous session were listed but none appeared when I tried selecting them. They must be hidden somewhere. I tried several work-arounds. The one that gives a result is by selecting in the View menu the Enter Full Screen item, then try to go back to a normal view which is a pain in the neck. Is there a clean method to make all those windows come back to their normal position and if possible preventing FF from doing this in the first place? TIA Nick

Firefox 153.0.4 on MacOSX 26.5.2 on a 2021 M1 Macbook Pro.

2 finger scroll barely works, it's very laggy. Sometimes 3-5 seconds after the physical movement.

Change: Settings -> Displays -> Promotion (set back to 60hz) fixes it.

So far no messing with about:config settings has fixed things. Turning on / off smooth scrolling makes no difference. Turning on / off hardware acceleration doesn't change anything,

Seems like a recent bug.

Hi Team,

In Firefox, the close button is only partially clickable and is not accessible on the right side. However, when I hover over it, a square background appears around the button. Could you please take a look?

Thank you

I updated to version 153.03. As a habit, before I close firefox I always clear browsing data. After the update, when I click "clear" to clear browsing data, the website freezes every time. I have to force quit to exit the website. I have macbook, sequoia 15.7.3

I have noticed for some time when I access Facebook the site reacts very slowly and hangs up frequently. When I access Facebook on the Chrome browser I don't experience the same problems. So, it appears my Facebook issue is a Firefox browser issue. Can anyone please help and explain how I can improve my Facebook experience while using Firefox. Appreciate any help. Thank you.

After updating to Firefox 153.0.1 on my 2026 MacBook Pro Silicon running Tahoe 26.5.2, my Firefox sidebar refuses to open, either by toggling the menu bookmark sidebar icon or pressing the shortcut keys.

Hello there,

I’m experiencing high memory and CPU usage in Firefox, which is affecting my computer’s performance. One issue appears to be that “FirefoxCP Isolated Web Content” continues running even when tabs are inactive, contributing to increased resource usage.

Other browsers, such as Microsoft Edge, reduce memory and energy consumption by putting inactive tabs into sleep mode after a period of inactivity. I would prefer to continue using Firefox as my default browser, but I need a way to manage this level of resource usage.

Could you please advise whether Firefox offers a comparable setting, workaround, or planned improvement to reduce CPU and memory usage from inactive tabs?

Thanks for your help!