Comment by cxr

The build process for the rest of Firefox could be as modular as devtools. When I was involved with Mozilla (and for a while after), it was a frequent criticism of mine that no one was prioritizing making the contribution process as easy as possible for people who didn't have an email address ending in @mozilla.com.

Zotero has (had?) a really cool build system. Zotero is written on an Electron-like architecture, except it uses a Gecko-based runtime instead of Blink. (Firefox is the same way and has always been this way, and this predates not just Electron, but Chrome/Chromium, too.) Similar to the way that Electron apps' build scripts generally work by downloading a prebuilt Electron (rather than requiring developers build it from source), Zotero works by downloading a release build of Firefox, unarchiving everything, sweeping away all the XHTML/XUL/CSS/JS that comprises the Firefox UI and application logic, and then swapping in the components that make up Zotero. (In other words, just how it should work 90+% of contributors who want to submit patches against Firefox nightlies, too.)