IMPORTANT: To use enterprise policies on macOS, you must set the EnterprisePoliciesEnabled policy.

An example plist file with all options is available here:

https://github.com/mozilla/policy-templates/blob/master/mac/org.mozilla.firefox.plist

This plist file is NOT a mobileconfig. It is intended to be input to a tool like Apple Configurator, Profile Manager, Jamf Pro or Intune. For my testing, I use https://github.com/timsutton/mcxToProfile.

In particular, in a mobileconfig, the configuraton must be nested in ```mcx_preference_settings``.

If you want to set specific options from the command line, we also provide flattened shortcuts to any item that is nested in the plist file.

For example, this policy:

{
  "policies": {
    "Homepage": {
      "URL": "http://example.com/"
    }
  }
}

which would be set in the plist file like this:

<key>Homepage</key>
<dict>
  <key>URL</key>
  <string>http://example.com</string>
</dict>

Correctly writing the nested value with the defaults command can be hard, so you can flatten the keys by separating them with __, like this:

sudo defaults write /Library/Preferences/org.mozilla.firefox Homepage__URL -string "http://example.com"

Before any command line policies will work, you need to enable policies like this:

sudo defaults write /Library/Preferences/org.mozilla.firefox EnterprisePoliciesEnabled -bool TRUE

If you want to set user specific policies, use ~/Library without sudo:

defaults write ~/Library/Preferences/org.mozilla.firefox EnterprisePoliciesEnabled -bool TRUE
defaults write ~/Library/Preferences/org.mozilla.firefox Homepage__URL -string "http://example.com"

If you find that Firefox is not using your updates immediately, you can run:

sudo defaults read /Library/Preferences/org.mozilla.firefox