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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?

Hello,

i was trying to check my apparmor stuff because of the warning on Linux. Now i tried duck.ai to instruct me , but created more damage than anything else. It said to set firefox in enforcement mode, now it wont start (well im using Firefox right now in complain mode)

How do I fix this problem that everything runs normally and safe?

Please help me! madmorph666@madmorph666-E14301:~$ sudo aa-complain /usr/bin/firefox /usr/bin/firefox wird in den Complain-Modus versetzt. madmorph666@madmorph666-E14301:~$ firefox ATTENTION: default value of option mesa_glthread overridden by environment. [Parent 72019, Main Thread] WARNING: gtk_widget_get_clipboard: assertion 'gtk_widget_has_screen (widget)' failed: 'glib warning', file /builds/worker/checkouts/gecko/toolkit/xre/nsSigHandlers.cpp:201

(firefox:72019): Gtk-CRITICAL **: 03:12:17.894: gtk_widget_get_clipboard: assertion 'gtk_widget_has_screen (widget)' failed [Parent 72019, Main Thread] WARNING: gtk_clipboard_request_contents: assertion 'clipboard != NULL' failed: 'glib warning', file /builds/worker/checkouts/gecko/toolkit/xre/nsSigHandlers.cpp:201

(firefox:72019): Gtk-CRITICAL **: 03:12:17.894: gtk_clipboard_request_contents: assertion 'clipboard != NULL' failed [Parent 72019, Main Thread] WARNING: gtk_widget_get_clipboard: assertion 'gtk_widget_has_screen (widget)' failed: 'glib warning', file /builds/worker/checkouts/gecko/toolkit/xre/nsSigHandlers.cpp:201

(firefox:72019): Gtk-CRITICAL **: 03:12:17.894: gtk_widget_get_clipboard: assertion 'gtk_widget_has_screen (widget)' failed [Parent 72019, Main Thread] WARNING: gtk_clipboard_request_contents: assertion 'clipboard != NULL' failed: 'glib warning', file /builds/worker/checkouts/gecko/toolkit/xre/nsSigHandlers.cpp:201

(firefox:72019): Gtk-CRITICAL **: 03:12:17.894: gtk_clipboard_request_contents: assertion 'clipboard != NULL' failed [Parent 72019, Main Thread] WARNING: gtk_widget_get_clipboard: assertion 'gtk_widget_has_screen (widget)' failed: 'glib warning', file /builds/worker/checkouts/gecko/toolkit/xre/nsSigHandlers.cpp:201

(firefox:72019): Gtk-CRITICAL **: 03:12:17.894: gtk_widget_get_clipboard: assertion 'gtk_widget_has_screen (widget)' failed [Parent 72019, Main Thread] WARNING: gtk_clipboard_request_contents: assertion 'clipboard != NULL' failed: 'glib warning', file /builds/worker/checkouts/gecko/toolkit/xre/nsSigHandlers.cpp:201

(firefox:72019): Gtk-CRITICAL **: 03:12:17.894: gtk_clipboard_request_contents: assertion 'clipboard != NULL' failed [Parent 72019, Main Thread] WARNING: gtk_widget_get_clipboard: assertion 'gtk_widget_has_screen (widget)' failed: 'glib warning', file /builds/worker/checkouts/gecko/toolkit/xre/nsSigHandlers.cpp:201

(firefox:72019): Gtk-CRITICAL **: 03:12:17.894: gtk_widget_get_clipboard: assertion 'gtk_widget_has_screen (widget)' failed [Parent 72019, Main Thread] WARNING: gtk_clipboard_request_contents: assertion 'clipboard != NULL' failed: 'glib warning', file /builds/worker/checkouts/gecko/toolkit/xre/nsSigHandlers.cpp:201

(firefox:72019): Gtk-CRITICAL **: 03:12:17.894: gtk_clipboard_request_contents: assertion 'clipboard != NULL' failed ATTENTION: default value of option mesa_glthread overridden by environment. ATTENTION: default value of option mesa_glthread overridden by environment. ATTENTION: default value of option mesa_glthread overridden by environment. ATTENTION: default value of option mesa_glthread overridden by environment. ATTENTION: default value of option mesa_glthread overridden by environment. ATTENTION: default value of option mesa_glthread overridden by environment. [Child 72430, Main Thread] WARNING: Unable to open /var/lib/flatpak/exports/share/dconf/profile/user: Keine Berechtigung: 'glib warning', file /builds/worker/checkouts/gecko/toolkit/xre/nsSigHandlers.cpp:201

(/usr/lib/firefox/firefox-bin:72430): dconf-WARNING **: 03:12:53.181: Unable to open /var/lib/flatpak/exports/share/dconf/profile/user: Keine Berechtigung ATTENTION: default value of option mesa_glthread overridden by environment. ATTENTION: default value of option mesa_glthread overridden by environment. ATTENTION: default value of option mesa_glthread overridden by environment. ATTENTION: default value of option mesa_glthread overridden by environment.

I originally deleted Firefox by accident and have downloaded it via Microsoft Store. All seems well then after I click on the app to open it, I Get the ‘Windows cannot find C:\Program Files\Mozilla Firefox\firefox.exe. Make sure you typed the name correctly, and try again’ for ‘Firefox’ error how can this be corrected?

Hello, I’m having trouble getting Firefox to work properly on my computer. During installation, the setup process becomes very slow, and once I manage to install it, Firefox hangs or becomes unresponsive within a few seconds after launching.

My system details:

Operating System: Windows 10 64-bit

What I’ve tried so far:

Reinstalling Firefox Running in Safe Mode Clearing profile data Disabling antivirus temporarily

None of these steps solved the problem. There are no specific error messages — the browser just freezes, and I have to close it via Task Manager.

export GDK_BACKEND=x11 MOZ_ENABLE_WAYLAND=0 MOZ_DISABLE_WAYLAND=1; /mnt/bootdrive/firefox3/firefox/firefox -P tx1p72s0.dev-edition-default XPCOMGlueLoad error for file /mnt/bootdrive/firefox3/firefox/libxul.so: /mnt/bootdrive/firefox3/firefox/libxul.so: undefined symbol: gdk_wayland_device_get_wl_seat Couldn't load XPCOM.

Has support for X11 been removed?

I am still using Win 7 but converting to Win 11. The most recent "patch Tuesday" update from MS killed Office 2016. Since then Fire Fox will occasionally pop up the "Couldn't load XPCOM." (no file extension) warning. It may do this when opened but not always. Can also occur in the midst of a session.

Program seems to be working correctly but some of my pinned locations disappeared when this started. New locations are retained between sessions. Is there a problem with continued operation with this warning? Is there something that I can do to repair it.

Howard Neuschaefer [email removed]@sbcglobal.net

I know that this is not a new issue, but it's a recurrent issue that keeps coming back. When I install a Firefox update, MacOS (15.5 at present) often gives me a popup that says "Firefox is trying to install a new helper tool. Enter your password to allow this."

But I don't ever want to enter my password to install a tool that doesn't identify itself. I view Firefox as always being at the forefront of security, but asking for a password for a tool that's not identified is a security risk. Maybe it's MacOS that refuses to identify the "helper tool", but it's a Firefox problem. It's unacceptable.

In today's update, Firefox won't work at all after I hit cancel to the password dialog. I have to Force Quit it. I'm going to have to delete Firefox and reinstall, and hopefully that will work. But I shouldn't have to do this. It's unacceptable that this keeps happening. (If there's some weird configuration issue at my end, I think Firefox should be flexible enough to deal with it.)

I don't know what version of Firefox is generating the problem, because it's currently unresponsive, since I haven't entered my password to install the helper tool. (I'm writing this in Safari.)

(In the attached image, I blotted out my username.)

When trying to launch the browser from a network folder, I encounter the errors shown in the screenshots. If I launch the browser on one computer, everything is ok, but if I need to launch it on at least the second one, I encounter this error until I close the browser on the first one. I don’t know what could have happened, because I didn’t touch the configuration and everything worked fine for us last year. Nothing was updated or changed. Firefox Portable ini file configuration:

Hello,

Recently, (past month or so) I have had difficulty opening Firefox on my PC. Found suggestion of renaming the .exe which did work, but now it will not open AT ALL. Uninstalled, and re-installed. nothing. Renamed .exe. Nothing. It will OPEN as admin, but cannot access any settings or browse. I am at a loss, and really do not want to go back to Chrome.

Previously attempted uninstalling ESET antivirus and Defender, and still would not open.

Thank you!

-Tim

There always seem to be daily issues, "Mozilla Not Responding". We clear out Cookies, Cache, history, etc. throughout the day. We've had to shut it down and restart the computer. Oftentimes, the system just shuts down.

For the last few weeks, we have an unknown popup from Mozilla, "Unable to load XP.com". Not sure what this may be or why this popup suddenly started. We close it and pops up periodically several times in a day. I am attaching a screenshot of the image.

Thanks

Firefox was working perfectly up until this morning and I'm pretty sure there wasn't a new update today. But now when I open the app a new window will briefly pop up for a fraction of a second and then disappear. Unfortunately this prevents me from accessing troubleshoot mode or crash reports so i can't provide much information on specifics.

I followed the steps here: https://support.mozilla.org/en-US/kb/firefox-keeps-crashing-startup and they haven't worked so far. I tried a clean install and restarting my computer multiple times, but no dice. There also don't seem to be any compatibility issues with the most recent version in the release notes.

I always use Firefox Private Window when I go on the Internet. Today, while I was on Fidelity.com, I was suddenly logged out. When I tried to go back to Fidelity.com using Firefox/Private Window, a dialog box on Microsoft Edge appeared asking me to: "Choice: #1 Do you want to make Firefox to be your default" "Choice: #2 Not Now". Which ever I choice I choose, Microsoft Edge will appear with the two above choices. This has been happening repeatedly for several minutes now, so I tried to reach Firefox Support.

My main problem is I cannot access Firefox / Private Window anymore since I was suddenly logged out of Fidelity.com.

Would you please fix this problem. Also, I already selected Firefox to be my default browser long time ago. Why am I being this question every time I go on the internet using Firefox?

Whenever I close Firefox and try to reopen it, it brings up a system error that says, "The code execution cannot proceed because C:\WINDOWS\system32\pmls64.dll was not found. Reinstalling the program may fix this problem." I've tried completely deleting Firefox and reinstalling and it opens a new tab, but when I close it i get the same error message.

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After my pc has been on for a while, seemingly random duration, Im not able to open firefox anymore. For example if clicking on a link in discord, or if I close the browser and want to open it again. I've tried refreshing and reinstalling but that didn't help.

I have an M1 Macbook Pro running macOS 15.5 (24F74). Often after booting up my laptop when Firefox launches it freezes. When I long press on the Firefox icon it says "Application is not responding".

I found this post: https://www.reddit.com/r/firefox/comments/1fi4p94/firefox_freezing_on_start_on_macos/ which mentions an incompatibility with Firefox and Adobe Creative Cloud. Sure enough, when I quit Creative Cloud Firefox starts successfully.

Anyone have any ideas of what's causing this?