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On one macOS Sonoma machine, Firefox launches very slowly and then crashes. On another Mac with the same macOS version, Firefox works normally.

Even in Safe Mode, Firefox cannot start its GPU and socket subprocesses. Steps to Reproduce 1. Download the latest Firefox from the official Mozilla website. 2. Install it normally in /Applications. 3. Launch Firefox by double-click or from terminal. Firefox starts very slowly and then crashes or becomes unstable.

When launching Firefox in Safe Mode: /Applications/Firefox.app/Contents/MacOS/firefox --safe-mode [Parent 1846, IPC I/O Parent] WARNING: Failed to launch gpu subprocess @MachCheckInListener TimedOut (Error:0) [Parent 1846, IPC I/O Parent] WARNING: Failed to launch socket subprocess @MachCheckInListener TimedOut (Error:0) [GFX1-]: Fallback remains SW-WR [GFX1-]: Failed to launch GPU process after 3 attempts

• Reinstalling Firefox does not fix the issue. • Safe Mode does not fix the issue. • The problem appears to be related to Firefox child process initialization (GPU and socket processes). • The browser often starts in crash recovery state. • Automation tests fail with: “Browsing context has been discarded”

Firefox is currently unusable on this machine due to repeated crashes and inability to initialize required subprocesses. • Any recommended workaround or diagnostic steps.

Hello, I have installed the latest Firefox on my Windows 11 desktop PC. I have created a shortcut to Firefox in the start menue Since a few week, I observed that I had to invoce Firefox twice in order to get is running once. The same happens if I double-click on firefox.exe in the intallation folder (C:\Program Files\Mozilla Firefox): After the first double-click, the windows activity circle appears for a few seconds and then dissapears again (without staring Firefox). After the second double-click, Firefox starts immediately.

I can repeat this several times.

• first double click > nothing happens
• second double click > Firefox starts
• closing Firefox
• third double click > nothing happens
• fourth double click > Firefox starts
• closing Firefox
• fifth/seventh/... double click > nothing happens
• sixth/eigth/.. double click > Firefox starts

I have no idea what might have gone wrong. Any suggestion from the community is appreciated. Best,

Hello I had Mozilla Firefox as my default browser on my Mac laptop

I got a message this morning that Firefox could not open

I tried several times but no luck

I read through some of the online HELP sites and deleted the Firefox app and reloaded it

I also cleared the browsing history on SAFARI and CHROME although I couldn't see why that would work

Still not able to get FIREFOX to open

After upgrading to version 144 in Windows 11, the portable version of firefox stopped opening, the splash screen appears and shuts down. If you run firefox.exe, it works, but the portable program itself crashes and won't start. There is nothing in the logs, antivirus is off, windows security is turned off. How to fix this?

Hi, after clicking FF icon, I got nothing. Profile manager (firefox.exe -P) does not start. In event viewer there is log: Name of the application causing the error: firefox.exe, version: 147.0.0.11, timestamp: 0x695c3722 Name of the module causing the error: unknown, version: 0.0.0.0, timestamp: 0x00000000 Exception code: 0xc0000005 Fault offset: 0x00007ffc561c6160 Faulting process ID: 0x4A54 Startup time of the application causing the error: 0x1DC85EE68CB3BAD Faulting application path: C:\Program Files\Mozilla Firefox\firefox.exe Faulting module path: unknown Report Id: e599c553-d77c-4b73-a863-1ccaa8d3bd4c Faulting full package name: Faulting relative application ID for package:

Last time deleting profile was helpfull, today nothing helps... Reinstall - the same... Any ideas?

I am unable to open my profile on Firefox. I am using desktop and windows 11. I am typing this question on DuckDuckGo browser because I was unable to go in. It will not let me search, open new tabs, refuse to open new tabs and even to click on settings. I also tried to delete it in an attempt to log in again but it won't even let me delete it. The image I shared is all I see. No bookmarks, shortcuts, ways to do settings and other things. Thank you!

I have tried all the troubleshooting steps of uninstalling, reinstalling and backing up my profile but on every machine after one session or one time instance and if I have to close Firefox or restart my workstation, I can no longer launch Firefox. It leads me to believe there is some kind of profile issue or corruption with my account but for months I've been battling this issue and can not resolve it. I do remember getting some Firefox window showing the Profile option or Create Profile and I believe nothing was selected. I proceeded to select the Profile on the left and it seems after that is when all the problems started to occur. If anyone has experienced this or can assist, I would greatly appreciate it.

I'm a Mac user on desktop. Something happened to my Firefox about two weeks ago. I was able to bring up Firefox which had all my bookmarks, passwords, etc. What is different is that I can not bring up Firefox by hitting the icon in the dock. If Firefox is already up and I hit he icon, it will jump to the front. But not if it is sitting in the dock.

Application error: a client-side exception has occurred while loading (see the browser console for more information).

where is the browser console? how do i fix it never had an issue with until the last two days?

Greetings Ya'll,

I have to apologize if this is a double post, but I came back to the forum, & wanted to see if there were any responses, but i could only find my post listed under "My Profile"/"My Questions".

My original post was made Dec. 19-2025

=======================================

Early this morning as I went to use the Firefox browser, on My Desktop, I got an update, & then firefox opened, somewhat.

The homepage did not fill in with favorites, suggestions, etc, and in fact all that did load was the Search bar, but not one of my usual website buttons. The "edit", "help", etc. buttons at the upper left hand corner did load, but that is all. Not one of the buttons work, nor can I close out the Firefox page, by tapping the "X" in the upper right hand corner.

The only way that I could close out the "Firefox Page" was by going through the "Control/Alt/Delete" & then "Signing Out", which would initiate a "Re-start". Once I signed in, I could return to the Desktop, where everything works.

I use Firefox as my Browser on my Android phone, & at this moment, I've not had any problems using Firefox on my Cell Phone.

The only way that I could get to the Mozilla Website was by using the Microsoft Edge Browser, which is not giving me any problems as far as accessing the Internet!

How can I correct this problem, & go back to the Firefox Browser?

Through extensive troubleshooting, I am unable to get firefox to open at all.

I've done a full uninstall, cleaned all user directories, program files / x86, program data, appdata roaming and local, etc. I used the Microsoft uninstaller and even Revo Uninstaller to remove everything related to Firefox, did a restart and reinstall of the latest one and it still won't launch.

Firefox was previously working until a reboot occurred and now it won't launch.

Firefox 32 bit seems to work when installed, and running Firefox as an admin previously worked but no it no longer does.

I looked at the following articles: - https://support.mozilla.org/en-US/kb/firefox-wont-start-find-solutions - https://support.mozilla.org/en-US/kb/profile-manager-create-remove-switch-firefox-profiles - https://support.mozilla.org/en-US/kb/profile-manager-create-remove-switch-firefox-profiles#w_start-the-profile-manager-when-firefox-is-closed

There's no malware on this machine (business EDR on it, even disabled it as a test and it still didn't open).

I was able to launch the profile manager but now I am unable to as the processes launch in task manager and then within 5 seconds they close.

Firefox is not running in the background for any user (I'm the only one logged in after a reboot as well)

I'm unable to open in troubleshoot mode either. Tried run as and admin cmd "C:\Program Files\Mozilla Firefox\firefox.exe" -safe-mode

Ran SFC / scannow / DISM restore health commands as well and both came back fine / no integrity violations