Apple has officially seeded the third developer beta for macOS Sierra 10.12.3, three weeks after seeding the second 10.12.3 beta and almost a month after releasing macOS Sierra 10.12.2, the second update to the macOS Sierra operating system.
According to Apple’s release notes, the 10.12.3 update “improves the stability, compatibility, and security of your Mac.” No specific changes, bug fixes, or feature additions were discovered in the first two betas, but we’ll update this post should any new features be found in the third beta.
The beta software is available through Apple’s dedicated developers page, and can be downloaded from there. It is also available as an over-the-air (OTA) update on registered devices running the first beta.