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Hello,

I have several PC;s but all suffer on occasion absurdly slow performance when a Firefox update is released.

I may be wrong but it appears there are too many of these processes running, I tried changing the value in " about:config " but Firefox defaults the value back to " 12 " when the browser is restarted.

" app.normandy.migrationsApplied 12 "

The below details are from a small, new cube pc that runs great, it is slow but does perform well, even previously just the other day running multiple Live Youtube streams with no issues, until now. :)

Any help would be great. Thank you!!!

" Firefox 142.0.1 (64-bit) "

Device Name Garage Processor Intel(R) Celeron(R) N4020 CPU @ 1.10GHz 1.10 GHz Installed RAM 4.00 GB (3.83 GB usable) Storage 58 GB SSD VID:32 MMC64G Graphics Card Intel(R) UHD Graphics 600 (128 MB) Device ID C12EB49A-0C22-41C3-A8E6-4420E4A419B0 Product ID 00330-50441-82637-AAOEM System Type 64-bit operating system, x64-based processor Pen and touch No pen or touch input is available for this display

I've searched other forums and I am not having any luck. If I open 1 Firefox browser then 10-15 open instances will show up under Task Manager. They load automatically. This slows down everything and I have to delete the excess browsers. Would you please offer some advice? Thank you in advance.

Hi, I’ve noticed that Firefox often uses a lot of memory when I have multiple tabs open, even more than Chrome or Edge on the same number of tabs. Sometimes it slows down my system or makes switching between tabs laggy.

Is this normal behavior, or is there a way to reduce Firefox’s RAM usage without losing performance? Are there specific settings, add-ons, or troubleshooting steps I should try?

Thanks in advance!

Hi,

I'm using Powertoys Keyboard Manager to start Firefox from keyboard Shortcuts. It work almos perfectly except for focusing the newly started window.

The windows opens well, but i' have to click in it to take the focus of it, otherwise i can't type in address bar for example.

I tried to add -foreground in the shortcut parameters, but still not working.

Any idea ?

Thank you very much.

Since a while, I think it is since I created an extra testprofile with "firefox-esr -P", but I've set my main profile as default again

When opening a link in another program than firefox I get always: a popup "Close Firefox" "Firefox is already running, but is not responding. To use Firefox, you must first close the existing Firefox process, restart your device, or use a different profile."

I do have both firefox and firefox esr, I usually use regular firefox the second came with the debian 13 repository.

I keep the esr to test display issues for reproducibility on my personal desktop, because I manage debian 13 kiosk-style desktops with firefox-esr.

(I noticed also that the regular firefox profiles can not be opened in firefox esr, so I use an extra profile for esr)

Top bar reappears after page scrolled down, preventing further scrolling, but when releasing finger at the top of the screen the bar completely disappears and doesn't come back.

149.0a1 (Build #2016141823), 62b991cbf35038109ba97ee21e4de10476194d9a GV: 149.0a1-20260203210813 AS: 149.20260203050225 OS: Android 16

I have Firefox (always updated to the latest version) and I have noticed a memory leak that EATS up RAM. I have 1 tab open, playing a set spotify playlist. within 24 hours of rebooting the machine, Firefox has swallowed 7gb of my Memory as shown in Activity Monitor/Memory Pressure. I've been having this issue for some time, updates to MACos make no difference either. NO other program does this. I've tested the same playlist in other browsers, Chrome, Safari, uses 1gb, brave/opera uses less than 500mb and they've been open for over a week. This memory leak is a bug in Firefox. I've seen it before (other software, mainly on Windows) but never like this on a Mac......How do I escalate this?

Roblox was blocked on my device and I wanted to get it unblocked and play it on Infrexa with Firefox. I already followed steps mentioned on the official webpage: https://www.infrexa.com/now-gg-roblox-login-and-play-roblox-unblocked-on-your-browser so please don't advise similar troubleshooting methods.

Now I am able to play roblox but the problem is that when I play the Roblox through "Mozilla Firefox" it shows an error "Firefox is already running but is not responding" and then becomes unresponsive when pressing refresh button, the fan gets faster and device heats up with too much hanging. But when I open the Roblox through "Chrome" it comparatively works good and asks for login details and after redirection it allows me to play Roblox Unblocked without any issue. "Roblox unblocked" here simply means a technical sense, meaning “not crashing” or “free from software or network errors and or browser malfunction".

I have been using Firefox for a long time and my passwords and user ids are saved in the browser so I want to continue using "Firefox" as default browser but I am having the issue in playing roblox unblocked and other games through Firefox browser. I think the current issue that I have started facing is especially after a recent windows update.

I also tried many other gaming platforms like Official Roblox.com, Now.gg Roblox, easyfun.gg and web.cloudmoonapp.com but all of them faced same issues on Firefox while running ok on Chrome.

I am currently running Windows 11 (25H2 Licensed version). I want to play roblox unblocked on my device using Firefox (updated). My parents have already allowed me to play Roblox and I am playing it on my own device and internet connection. Please fix the browser issue and unblock Roblox for me. Please also check my browser version against Windows 11 compatibility if possible.

If you fix this issue for me, I will be grateful to you.

When typing to search, address etc keyboard inputs are not being accepted. The typing here is fine but attempting a search or entering a url or even the space bar nothing happens.

Dear Firefox Support Team,

I am writing to report an issue I’ve been experiencing with Firefox on my MacBook Air (M3, 8GB RAM). Recently, Firefox has been becoming unresponsive quite often, and the Activity Monitor shows significantly high memory usage. For context, I typically have two Firefox windows running simultaneously, with approximately 5 tabs open in each window (10 tabs total). This is when I notice the performance degradation and high memory usage.

To help you investigate, I’ve attached:

• A screenshot of the memory usage in Activity Monitor when Firefox is running.
• A screenshot of the extensions currently enabled in Firefox.

I am open to suggestions, such as disabling or removing certain extensions if they might be causing conflicts. However, I wanted to report this issue first to understand if this is a known problem or if there are optimizations planned for Firefox on Apple Silicon Macs.

Let me know if you need additional details, such as Firefox version, macOS version, or specific steps to reproduce the issue. I’d be happy to provide any information that can help resolve this.

Thank you for your time and assistance. I look forward to your response.

Best regards, Hemant

This is happening more frequently. sometimes clicking links works but the cursor will not respond if i hover over the new tab button. To continue I have to select a new firefox window, The unresponsive window remains in error even when a new working window is active.

The lack of a title bar makes it impossible, for example, to close the application by pressing the "X" icon in the upper right corner. The title bar does not appear when the application starts, but does appear when the application window is minimized and then maximized.

Dear Firefox Support,

Since yesterday, I’ve been experiencing an issue where the entire browser randomly freezes for a few seconds. When this happens, everything stops — I can’t open or close tabs or windows, and I can’t type in the address bar. If I’m typing something when it freezes, the input seems to be stored in the background and then appears all at once after about 5 seconds, when the browser becomes responsive again. All add-ons are disabled, the computer has been restarted, and the latest version of Firefox is installed. This issue started just yesterday — before that, everything was working perfectly. No new programs were installed, and all other applications on my system are functioning normally. When I switch to Chrome, there are no issues at all. Thank you for your help.

Best regards, Peter

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.

When switching apps from Firefox to other apps, it almost always reloads the webpage. This is annoying in the certain scenarios

1. After I enter my username, it goes to a password page. I switch app to my password manager to copy my password. Comes back to Firefox and it refreshes, going back to username screen. Impossible to login. 2. After I enter my username and password, I need to go to SMS or Outlook app or Authenticator app to obtain the MFA code. Comes back to Firefox and it refreshes, going back to the login screen. Impossible to login.

This happens to various websites. I have no issue with Chrome or Brave on the same phone. I even tried terminating all apps leaving with just Firefox and the same symptom happens. Memory is sufficient, my phone has 12GB of RAM.

I used camera inside a tab and then closed the tab. I get the "Tap to open the tab that's using your camera." notification. If I tap it redirects me to home page in Firefox. If I swipe right or left won't close the notification (seems to be glued).

It's the second time I'm confronting this. It disappears only if I restart the phone.

I can complete the sign in and enter my password, and then I get a spinning wheel and can no longer click on the tabs or minimize the window. I have to force close it and it shows as not signed it. I've also tried signing in using my phone and the QR code, same thing. This happens with or without 2FA, I turned it off and the issue persists. Everything else about the browser works completely but I can't sync across devices without the Mozilla login working.

when I type in the search bar of Firefox I have to double tap the space bar to get a single space. quiries for solutions tell me to toggle a non existent option. tried different soft keyboards still happens. turned off predictive text on Samsung keyboard and it solved the space bar problem but I would rather switch browsers then turn predictive text. been using Firefox for decades don't really want to switch this issue will make me.

(My laptop is very slow. I have cleaned the cashe, performed disc cleanup, cleaned the memory, and everything i can think of. I opened task manager and see that multiple instances of Firefox open. (photo #1) I have uninstalled and reinstalled to no avail. I have also tried changing the preferences to 1 instance, but it wont allow me to. (photo #2) Please help.