Mozilla's biggest export is Firefox, and with Windows 8 having been in circulation for a few months now, the next stage of preparations for a version of the popular browser tailored to Microsoft's latest OS release have begun. Last week, the Metro/Modern-ized browser reached Mozilla's nightly build channel, and today, it has reached Mozilla-central. Although Firefox desktop product manager Asa Dotzler confessed there is still "plenty of work" to be done, it has now reached a point where it is stable enough for regular testing.