Firefox Community Forum

I don't use Firefox daily, so not sure exactly when it last opened ok on my iMac (26.5.2). So I downloaded Version=153.0.1 BuildID=20260727124451, and tried again. When attempting to launch, the icon in the dock bounced a few times, then nothing. When repeated, it only bounces once.

Likely unrelated, but I had very recently upgraded my LuLu app (4.4.3) from Objective-See. It monitors outbound connections. But disabling the app changes nothing.

I'm not a MacOS guru. I expect there is an error in a log file somewhere that reveals the problem, but I don't know where to look.

Suggestions?

I had two profiles, was in the process of trying to learn how to use the 2nd profile (as seen in the link below), which I still have no answer for. Somehow, maybe I held down SHIFT for too long and clicked on something by accident, idk, but somehow, I ended up REFRESHING the 2nd profile, causing it to delete everything I had done with it, and it backed up the old profile onto my desktop in the process. I figured I could just simply delete the new profile folder it had created and put back my old profile in the profile folder, but now, Firefox will not open at all, saying "Your Firefox profile cannot be loaded. It may be missing or inaccessible." How do I get it to recognize the profile folders again? OMG, I'm using Microsoft Edge, please, get me out of this!

https://support.mozilla.org/en-US/questions/1479231

I launch Firefox from a shortcut in the QuickLaunch bar. I need to double-click that to get a response. But then TWO instances of Firefox open, and I have to close one - which seems a waste of time and effort over and over and over. My system is x32Win10ProV22H2. How to get just one instance ?

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?

Firefox 146.0.1 crashes every time upon launch (basically fails to launch), even in troubleshooting mode, with exception code 0xc0000005. Prior to today, it was working fine. Windows does not show any updates made over the last couple of days. I am on Windows 11 25H2, and I'm current with updates. Chrome works. Edge works. I logged on to the same computer as a different user (different profile folder in the user AppData folder) and Firefox still does not work. I tried to refresh Firefox and that did not resolve the issue. I tried to uninstall and reinstall Firefox and that did not resolve the issue. I tried to run DISM and SCANNOW and that did not resolve the issue. No issues are detected with a virus scan. I am stumped - please help!

As title: after running updates, Firefox consistently crashes when launching.

To give more concrete details:

-Running on Linux, specifically KDE Fedora 42. Firefox was updated to 142 from 141, alongside various other updates. -When launching Firefox from any source (directly, through a link, through the terminal etc.), the only window that appears is the crash reporter. -This issue occurs when launching in safe mode. Removing and reinstalling Firefox, including deleting the entire .mozilla folder in Home at the same time does not resolve the issue. I am unable to test rolling Firefox back to 141. -When attempting to launch from the terminal (safe mode or otherwise), the following is output (personal info redacted):

restorecon: SELinux: Could not get canonical path for /home/[username]/.mozilla/firefox/*/gmp-widevinecdm/* restorecon: No such file or directory.

/usr/include/c++/15/array:210: constexpr std::array<_Tp, _Nm>::value_type& std::array<_Tp, _Nm>::operator[](size_type) [with _Tp = HeaderBarButtonType; long unsigned int _Nm = 3; reference = HeaderBarButtonType&; size_type = long unsigned int]: Assertion '__n < this->size()' failed.

Redirecting call to abort() to mozalloc_abort

[ExceptionHandler generates a minidump etc.]

Gtk-Message: [timestamp]: Failed to load module "appmenu-gtk-module"

(I would note that to the best of my knowledge I had not included a plugin for decoding widevine in my Firefox setup, and certainly the Firefox 141 instance on the device being used to write this post (same OS) does not include it) -The crash files in the .mozilla folder, meanwhile, consistently list a segfault at address 0x0.

Any advice on diagnosing/solving this issue would be greatly appreciated. Let me know if there's any other information that would be helpful.

If it would be more appropriate, I could report this through Mozilla's bugzilla instance, but given the issue seems to be very niche (Fedora's ABRT shows a total of 5 unique affected users in the last few days) I am unsure whether flagging this there would be appropriate.

Today, I signed on to use my laptop, as usual, nothing different about how I sat down or anything, and I try to open Firefox and it flashes something on the screen, but I don't catch it as it immediately closes as well. It looked like a popup with a button, if that helps. I then try to open it again, realizing that I've got that bug, the one that causes browsers to open for a split-second and then close immediately, so I try to fix it how I fixed Opera GX before I stopped using that. Restarting? Nothing. Looking online for answers? Found some! I try starting it in Troubleshoot Mode, I can see down in my taskbar that Firefox is trying to open in Troubleshoot Mode but isn't. Okay, let's try something else, the Profile Manager. I use the Windows+R key to open the Run window and type in firefox.exe -p which according to a couple of websites, -This one included- should have opened the profile manager in a popup, but all I get is a flash of a window and nothing else. Then, I finally try uninstalling and reinstalling the app, upon reinstallation it asks if I want to keep my settings and whatnot, I say yes, problem persists. I uninstall and reinstall again, only this time declining the ability to keep my settings, the problem persists.

I'm extremely confused as to why nothing is working, and I don't want to have to reinstall Windows itself like I saw a comment on Reddit recommend, so if anybody has a slight idea of a solution, I'd be grateful, thank you in advance.

Edit: Just tried downloading and running Chrome, it worked for a second until it randomly closed, I know this isn't the support site for that browser, but I thought I'd mention that the "Not opening, just falshing for a millisecond" isn't just a Firefox thing for me.

I'm on Win10. This morning I see that MSLOP has updated my desktop PC overnight. FF was open before the update and attempted to restart but couldn't restore pages. I told it to start a new session and the PC blue screened. This has happened before so after the PC restarted I shut it down. It blue screened a few times while also trying to restart FF. I shut it down with the power button. FF will not start with troubleshooting (shift while double clicking on FF icon). It crashes and I get the crash window. Latest crash detail is below. What next? Any help is much appreciated.

UPDATE: I went to windows settings, apps, and clicked on uninstall for FF. Immediately a message box, "Would you like to refresh instead?" popped up. Sure, why not? It thought for a while and updated. I logged in again and I am back to a functioning 147.0.3. I logged into my bitwarden extension and ublock origin is still there. No clue what happened earlier.

Every so often for the past few days this "unfinished" program window has appeared on my pc on top of a normal Firefox window (see attached png). Does this have something to do with Firefox? I think the same thing appears when I first open Firefox, then it gets "filled in" and appears as a normal Firefox window. I am running Firefox 133.0.3 (64-bit) on Windows 10 Pro Version 22H2 build 19045.5247 Windows Feature Experience Pack 1000.19060.1000.0.

ExitException[ 3]javax.net.ssl.SSLHandshakeException: Received fatal alert: handshake_failure at sun.plugin2.applet.JNLP2Manager.downloadResources(Unknown Source) at sun.plugin2.applet.JNLP2Manager.prepareLaunchFile(Unknown Source) at sun.plugin2.applet.JNLP2Manager.loadJarFiles(Unknown Source) at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source) at java.lang.Thread.run(Unknown Source)

After an update minutes ago, Firefox immediately crashes on startup and crash reporter launches Rebooted computer. Launched firefox from command line with -safe-mode and -purgecaches

This is when the online help says to submit a report with the most recent bp-numbers. Thanks in advance for your assistance.

bp-2bd5243a-ff3d-4ea2-b0a2-ffb3d0260425 bp-28b30366-d7c1-46be-bc6b-1795a0260425 bp-e2aaa702-1190-4237-8ab3-7e5590260425 bp-93e9888c-569d-4148-b549-d97530260425 bp-d598e83a-3a9b-4874-b65a-ec7980260425

Hi,

I am using OS MX-25 Linux and after importing my previous FF profile from an earlier version of MX everything in Firefox 145.0 was fine: my bookmarks and extensions all loaded and everything was tickety-boo. However, after I attempted to relaunch FF I got the following message:

Your Firefox profile cannot be loaded. It may be missing or inaccessible.

I have tried numerous times to launch FF but just keep getting this message.

Eventually it launched, but after a while pages refused to load properly and so I closed it down. Since then, I have been unable to get FF to open.

Any help would be greatly appreciated.

Firefox has been working fine, but today when I clicked to start, I received an error message. "The file or directory is corrupted or unreadable." When trying to uninstall Firefox, Windows cannot find the uninstall helper. When I try to download a new version, I receive an error message: "Couldn't download - virus scan failed." Windows Security reports are all good. A scan found no viruses. Firefox will not open at all.