Apple on Wednesday seeded the first beta of macOS Sierra 10.12.3 to developers. The beta release comes just one day after the release of the macOS Sierra 10.12.2 update to the general public.
The first beta of macOS Sierra 10.12.3 – build 16D12b – is available for download via the Apple Developer Center, or via the “Update” tab in the Mac App Store.
At this point, we don’t know what new features and improvements are included in the new update. Apple’s official release notes merely say the new beta “improves the stability, compatibility, and security of your Mac.” We’ll let you know in this space as we find out any new features, changes, or bug fixes.