This add-on has a really simple functionality.
First of all, let’s forget the Active Directory. We come back later on that.
The basic idea behind the GPOFirefox is reading data from the registry and apply them to Firefox.
Thats it. That’s the description of the Add-on. That means, if you have the ability to deploy registry keys to your computers, you are in.
Registry keys can easily deployed by group policy, but that’s more or less a „soft“ requirement. If you want to maintain different configurations, use GPO. I have a documentation on how to create a GPO to deploy registry keys here.
Lets get deeper on how the add-on works
After Firefox is started, GPOFirefox reads the registry and applies all needed settings to your Firefox. There are two different type of settings you can define at the moment. Locked settings and so called default settings. The difference between both of them are as follows.
Locked settings: These settings are applied every time Firefox is started and are unchangeable by the user. If you want to set a default company startup page which is unchangeable, use locked settings. Some examples are proxy settings, disable updates, disable telemetry data etc…
Default settings: These settings are only applied if this key doesn’t already exist. If you want to set the initial default homepage for a new user / new Firefox profile but make it changeable from the user, use this one.