Firefox Enterprise Community Forum

We recently update Firefox with version 138.0 and now getting the message "Gah. Your tab just crashed" when opening the browser.

We attempted to update and install version 138.0.1 only resulting with the same error. We also found and attempted the following all resulting with the same error: - change the about:config page for settings to false for both browser.tabs.remote.autostart and browser.tabs.remote.autostart.2

- clear browser cache.

- enable Temporary Mode in the Help menu. This appears to fix the problem but only for the current browser session. When a new Firefox window is opened, the error reappears.

What is needed to resolve this error or is there a way to permanently enable Temporary Mode or some similar setting? Thanks for all your help with this.

Recently we've began installing Firefox 140.2.0esr to our environment via the .msi file that Mozilla provides, however we're running in to a very odd incident.

After approximately 24 hours from installing Firefox esr to devices, it appears that the application is "updating" to 141.0.3 on the "release" channel. As far as I'm aware, this shouldn't be possible to begin with. But we've applied these settings via GPO:

Computer Config > Policies > Admin Templates > Mozilla > Firefox Application Autoupdate = Disabled Pin updates to a specific version = Enabled = Set to 140.2.0 Background updater = Disabled Disable Update = Enabled Manual Update Only = Enabled

After applying the GPO, confirmed this appears within the registry:

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Mozilla\Firefox\ AppAutoUpdate = 0 AppUpdatePin = 140.2.0 BackgroundAppUpdate = 0 DisableAppUpdate = 1 ManualAppUpdateOnly = 1

At this point, I'm at a loss. We cannot have rapid release be what's installed in our environment. Is there something broken with 140.2.0 or are we doing something wrong here?

Hello,

New subscriber here. I have been given the task to test the install and uninstall of the Purview Firefox browser extension using Intune. I created 2 groups in EntraID, one for each (install and uninstall).

I have no issues with the installation. Initially, I left the test device in the install group and then added it to the uninstall group to remove it. (this usually works with other apps, it worked this way with the Purview Chrome browsing extension as well other apps) but when I do this, nothing happens.

Next, I removed the device from the install group and added it to the uninstall group only. Once the configuration profile applies to the test device, it allows the user to remove it manually (before it did not) but the extension remains installed.

I have created a policy using the administrative template extension uninstall option as well as with the OMA-URI settings but the same happens. When i check the device configuration for the device in Intune, it says it succeeded but that is not the case. The OMA-URI setting I was not too sure about, but gave it a shot. I used the UUID value for the Purview Firefox extension

I am attaching some pictures and hope someone can tell me what I am doing wrong. I can add additional information, if needed. I have opened a ticket with Microsoft last week but have not called me yet. I ran into this forum today.

Thanks in advance

Dear Team,

When my Client device installs From Firefox 102.7.0 ESR to Firefox 128.7.0 from SCCM. (The case is First install the Version 102.7.0 then save the Bookmarks and then uninstall. Second Install the 128.7.0 then check the bookmarks)

user profile Bookmarks are not mapped in Firefox. When I check C:\Users\Tests\AppData\Roaming\Mozilla\Firefox\Profiles I can see the xxxx.defaultesr

I don't understand why the bookmarks are not linked in Firefox. Can you please help? I would be thankful to you if you could share me the .bat script

Thank you

How do I lock the Microsoft Purview settings in the attached image using intune, so users cannot change them.

I have been able to make it that they cant disable or remove the extension but cannot figure out how to make it that they cant change the settings. I did try making a json file but it does not seem like Firefox uses it.

I have a lot of Firefox windows and tabs open, and I really don't want to lose my session.

I wanted to open a webpage in Firefox in fullscreen mode. But evidently there's some kind of serious flaw in Firefox that makes it incapable of opening webpages in fullscreen mode. Everyone says the only workaround is to open the webpage in kiosk mode. So I tried it.

But now I have two big problems:

1. One of my Firefox windows, with all its tabs, is stuck in kiosk mode. (Even if I close the window and then restore it with Ctrl+Shift+T, it's still in kiosk mode.)

2. All new Firefox windows I open with Ctrl+N are also stuck in kiosk mode.

I don't know what to do, and I'd really appreciate any help. Thanks!

I would like to know how the Firefox CVEs are affected on its version which are mentioned in NVD.

Let take mfsa2025-59, for example CVE-2025-8040, as per the NVD its says Firefox ESR < 140.1 is affected so does that mean it affect all the version which are lower than 140.1 which included the ESR 128 and ESR 115 versions or just the ESR 140 version series? then it raise on more question check this cve-2025-8029 in NVD it has specifically mentioned it only affect "Firefox ESR < 128.13, Firefox ESR < 140.1" and not the ESR 115 versions. Could anyone confirm it does not affect the ESR 115 versions or it affect all the versions? Now check this one cve-2025-8027, NVD clearly mentioned "Firefox ESR < 115.26, Firefox ESR < 128.13, Firefox ESR < 140.1" are affected so what I understand is that if the Firefox ESR 115 is vulnerable to any CVE it would be mentioned in the NVD specifically.

My point is that if any Firefox CVEs are listed in NVD and it specify only one version like “Firefox ESR < 140.1” what does that mean? Does it affect all the versions which include ESR 128 and ESR 115 or just the ESR 140 series version only affected? If any CVEs are affected on the ESR 115 and ESR 128 does Mozilla specifically mentioned those versions are affected right? Just like its mentioned in the cve-2025-8027

Any help would be appreciated to clarify this.

I am logged on to my Credit Union and attempt to download my statements. When using Firefox I get the message: {"Errors":["Authorization has been denied for this request."]}

When I contacted my CU, they said to add an URL to the Manage Exceptions. This worked, but I want to know why Firefox needs this but Chrome doesn't.

Hello,

support.mozilla.org/kb/website-translation says, when you do not have downloaded translation packs, parts of the packs will be downloaded when you first use the translation function.

My questions about this feature: - How does this work exactly? - Will the words from the website which i try to translate be collected and "downloaded"? - How are the translation language packs parted? - What information will be used and sent to servers/cloud to request these parts of the translation packs?

Thank you in advance for your help.

Best Regards

Bjoern

I don't understand why auto:config is so difficult (for me at least) to create. Isn't there an easier way? I've tried following the directions and creating the 2 files. But I can't manage to successfully create auto:config.

I created and pasted the first tile into the prefs folder. For the 2nd, I noticed the firefox.cfg file I created in Notepad appended a .txt suffix. I pasted it into the Firefox top directory. Then typed auto:config into the address bar. Nothing happened. Can anyone tell what I did wrong? Is the .txt suffix not recognized? Or is there's an easier way to do this?

We have Firefox deployed and managed through Intune/Endpoint and all works well but every device has an error with this line of the policy:

UserMessaging_FirefoxLabs [./Device/Vendor/MSFT/Policy/Config/Firefox~Policy~firefox~UserMessaging/UserMessaging_FirefoxLabs] STATE Error SOURCE PROFILES Source Profile Mozilla_Firefox_Configuration ERROR CODE 0x87d1fde8

The error code is the same on all devices and is the only one present in on each device config.

Does anyone have any idea what the issue and resolution would be?

Thanks, Matt

We are managing Firefox settings using Intune via Imported ADMX templates.

We are managing Extension Settings via 'Extension Management (JSON on one line)' which works fine for our force installs, force removals etc.

We have noticed that some users have installed 3rd party extensions which create the ExtensionSettings key in the registry with the 3rd party extension details.

The issue we see if when ExtensionSettings exists as a REG_SZ or REG_MULTI_SZ under `HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Mozilla\Firefox` it is then ignored if the `HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Mozilla\Firefox\ExtensionSettings` key exists.

Is there a setting we can use to have these settings merged by Firefox or have the REG_SZ/REG_MULTI_SZ take priority or is the only way to ensure enterprise policy continues to work we need to migrate our extension settings into the key rather than string?

Thanks!

Hi,

In the latest firefox update 149, no start pages are displayed that were distributed with a registry key via group policy. It only works again if you change this setting manually in the Firefox settings.

In Version 148 it´s fine.

Jan

I am having the same issue as this other user here: https://www.reddit.com/r/sysadmin/comments/17wvuwh/help_pinning_extension_in_firefox_with_gpo/

Preliminaries -- Initially (before trying to force-pin), I had these GPOs enabled:

Extensions to Install -> https://addons.mozilla.org/firefox/downloads/file/4410896/bitwarden_password_manager-2024.12.4.xpi

Prevent extensions from being disabled or removed ->

• {446900e4-71c2-419f-a6a7-df9c091e268b}
• {3f6129fb-6c55-4452-ab6f-7c109b2301df}
• https://addons.mozilla.org/firefox/downloads/file/4410896/bitwarden_password_manager-2024.12.4.xpi

(Those GPOs above all work.)

What I'm trying to do: Force-pin Bitwarden.

I believe I've followed the documentation correctly (except for not including a "*" case): https://mozilla.github.io/policy-templates/#extensionsettings

I've enabled this GPO with this value:

Extension Management ->

{

 "{446900e4-71c2-419f-a6a7-df9c091e268b}": {
   "default_area": "navbar"
 }

}

After running various "GPUpdate"s and whatnot, the option to uncheck "Pin to toolbar" is still available to click.

I've verified in "about:policies#active" that the JSON item appears next to "ExtensionSettings" and that there are no errors listed in the "Errors" tab.

I've also verified that it appears in the correct location in the Registry.

Since another user had the same issue (Reddit link above), I figured it'd be a good idea to check in with y'all to see if we are missing something.

Thanks for your help!

We are currently rolling out a profile management solution based on Ivanti User Environment Manager. In order to configure file includes and excludes in the profile management tool, we have to “standardize” the Firefox profile path in the filesystem. We have implemented a PowerShell script, which reads the currently used profile from %appdata%\Mozilla\Firefox\install.ini, renames the appropriate profile subfolder to “firefox.default-esr” and replaces the entries in installs.ini and profiles.ini.

The script seems to be reliable. However, for around 10% of the users, we are seeing issues when the user launches Firefox after the “firefox profile migration” happened. Firefox opens but none of the GUI controls is accessible. Firefox is completely unusable. See screenshot attached.

We do have workarounds to resolve this issue, such as completely wiping the %appdata%\Mozilla\Firefox folder and let Firefox re-build everything from scratch. But we are still trying to find the root cause the issue, because our customers have more than 100k clients, what will be a big impact and hard to handle for the helpdesk.

We are currently unable to reproduce the issue on test clients. Even copied Firefox profile folders form affected clients don’t show the issue on other clients.

Therefore we want to find out and ask for your help:

- Is there a supported way to “standardize” the filesystem folder name of the Mozilla Firefox (ESR) profile of a user? - What are the files within a Firefox profile that are required for the profile and the application itself to properly start? - Do you have any idea which files in a Firefox profile (in a corrupted state) could cause our issue?

Hi all,

We use a service integration in our organization that only works in the latest ESR version of Firefox (140.14). The latest regular release breaks our integration due to added security policies preventing the software from communicating with Windows services.

After installing the ESR version and disabling auto updates in the settings and adding the DisableAppUpdate registry key, the software still keeps updating to 154 (not the ESR version). I've also chosen to not install the Mozilla Maintenance service when installing the ESR version. I can't seem to find any support articles of people having the same issue. Is there something I may be missing? Any help would be greatly appreciated.

I've been tasked with removing Firefox from all Windows workstations in our enterprise environment. Our users don't have local admin, so when they install Firefox, it is installed in the user's profile.

I've just installed Firefox 143.0.1 in my own user profile for testing purposes. However, when I attempt to uninstall, either from Control Panel or by running %localappdata%\Mozilla Firefox\uninstall\helper.exe manually, UAC prompts for elevation, even though I installed without elevating.

I've dug in a bit more, and I found this was an issue five years ago as well:

https://support.mozilla.org/en-US/questions/1286070

According to that post, the issue was resolved, but it seems to have come back.

Any help would be appreciated.

How to get rid of "Your browser is being managed by your organization"? This thing is driving me crazy(er)! Please 'dumb down' your reply, as I am not computer literate. If it's a malicious attack, my anti-virus is not picking it up. Thanks!