the GPL does not actually require the sources to be published - they just need to be offered and available to anyone who wants them by some means that are not more demanding than how the binaries were acquired - if the binaries are published on a website, than publishing the sources on that same website is a very good way to make sure that happens
in this case though, i think the gnuzilla repo only contains build scripts - assuming that no parts of the gnuzilla repo becomes the browser itself, then the gnuzilla license probably does not apply to the mozilla sources - if you did not also publish a pre-compiled binary, you could probably stop at that i dont think the mozilla license requires sources to be offered; but the bigger concern with what your want to do is whatever is in the non-free software that is used to compile it - most likely some parts of that do become part of the browser - even if you did want to publish the complete sources, you can not, because you dont have them all also, notabug is intended for freely-licensed software only - the pre-compiled binary probably does not meet that criteria; which is the very reason why GNU does not publish them - i would write to the notabug admin asking for a special permission in this case -- http://gnuzilla.gnu.org
