Your first link is misleading because it's targeted toward onboarding new Firefox contributors and includes a Mercurial tutorial and development workflow guide in addition to build instructions. Simple build instructions are here:
https://developer.mozilla.org/en-US/docs/Mozilla/Developer_g...
On Linux I clone the source and run "./mach build".
Re:Feeling safer online with Firefox
by hackermailman on Friday January 13, 2017 @01:34PM
(#13393269)
Forgot to add there's a really good page around by the Chrome security team detailing all kinds of functions somebody might wish to remove such as dns lookups that expose your IP (the tails/torbrowser design document also has this list)
Re:Feeling safer online with Firefox
by putsteadywere on Friday January 13, 2017 @01:53PM
(#13393503)
do you have a link?
Then you make a custom mozconfig file to disable or enable features, or to add your own extensions (ie: windows): https://developer.mozilla.org/en-US/docs/Mozilla/Developer_g...
You can further abstract this with a mozconfig wrapper https://github.com/ahal/mozconfigwrapperBut I agree, I can't find any documentation what exactly every feature is and why you would not want to disable/enable them. The Chromium build process is much more straight forward, or you could just use 3rd party sandbox and regular release FF.