Because to put a build in F-Droid you need to write a build script to build the whole app from source on F-Droid’s VMs. You can’t, for example, fetch binary dependencies from Maven. You need to build them from source as part of your build process.
Android Firefox fetches a bunch of stuff from Maven as part of its build, some of which is proprietary libraries from Google to e.g. talk to Google Play Services or to Google’s trusted-hardware stuff, and some of which is the whole Gecko C++ source tree. Mozilla doesn’t want to pay their people to maintain two separate build systems for Firefox, one of which has to jump through a bunch of hoops.
Because to put a build in F-Droid you need to write a build script to build the whole app from source on F-Droid’s VMs. You can’t, for example, fetch binary dependencies from Maven. You need to build them from source as part of your build process.
Android Firefox fetches a bunch of stuff from Maven as part of its build, some of which is proprietary libraries from Google to e.g. talk to Google Play Services or to Google’s trusted-hardware stuff, and some of which is the whole Gecko C++ source tree. Mozilla doesn’t want to pay their people to maintain two separate build systems for Firefox, one of which has to jump through a bunch of hoops.
Then it just shows that they don’t “love OSS” as much as they say they do.