Your first link is misleading because it's targeted toward onboarding new Firefox contributors and includes a Mercurial tutorial and development workflow guide

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_guide/Build_Instructions/Simple_Firefox_build https://developer.mozilla.org/en-US/docs/Mozilla/Developer_g... On Linux I clone the source and run "./mach build".