There are (at least) two config files that seem to be made to define organizational preferences that should be valid for all users of firefox on a machine:
local-settings.js. Additionally, this guide talks about using ´all-companyname.js´.
It tried to define locked preferences by using ´lockPref´ in ´syspref.js´ as described here and here. However, then firefox complains about an unknown keyword. However, I can define the ´general.config.filename´ in both ´syspref.js´ or ´local-settings.js´.
And in addition, one can also define group policies, e.g. using the ´policies.json´.
So, my question is: Which of these possibilities should I use for which purpuse? Is there a good and up-to-date documentation that explains this?