Firefox for Enterprise Community Forum

We're exploring adopting a default deny policy for Firefox extensions in our enterprise. However when I tested this by creating a custom policies.json Firefox unexpectedly removed all extensions for me, including the ones I thought I had allow listed. Here is my policies.json but just keeping in the Facebook Container add-on to illustrate:

{

   "policies": {
       "ExtensionSettings": {
           "*": {
               "blocked_install_message": "Only approved Firefox extensions can be installed, please email your request to itdept@example.org",
               "installation_mode": "blocked",
               "allowed_types": ["theme", "dictionary", "locale"]
           },
           "@contain-facebook.xpi": { "installation_mode": "allowed" }
       }
   }

}

What I would like is to to allow pre-approved extensions (including if they already are installed) and all other types of add-on, but remove and prohibit installation of unapproved extensions.

Can anyone assist, please?

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!

I have a few questions regarding the auto-update policy of extensions installed via ExtensionSettings with the force_installed installation mode.

1. Can the extension receive auto-updates just like extensions installed through normal means? (e.g. extensions installed from https://addons.mozilla.org)
2. If so, will the user be notified when the extension requests new permissions?

In /Library/Preferences/org.mozilla.firefox.plist:

``` <plist version="1.0"> <dict> <key>EnterprisePoliciesEnabled</key> <true /> <key>ExtensionSettings</key> <dict> <key>cloudmetering@snowsoftware.com</key> <dict> <key>install_url</key> <string>https://raw.githubusercontent.com/SnowSoftware/agent-firefox-extension/refs/heads/main/cloudmetering-v1.2.3.xpi</string> <key>installation_mode</key> <string>force_installed</string> </dict> </dict> </dict> </plist>```

In about:policies: {"cloudmetering@snowsoftware.com":{"installation_mode":"blocked","install_url":"https://raw.githubusercontent.com/SnowSoftware/agent-firefox-extension/refs/heads/main/cloudmetering-v1.2.3.xpi"}}

The plist file did read "blocked" at one point, but it no longer does. Why isn't firefox picking up the new value from the plist file? Restarting/refresing FF has not helped so far.