As an "under-the-hood" release, performance was largely tied to the core technologies introduced in High Sierra:
For users coming from 10.13.2 (Build 17C205), 10.13.3 (17D47) was a relatively lightweight download (approx. 1.2GB to 2GB depending on the device). However, the post-installation behavior of the system told a different story of deep-level optimization. Mac OS High Sierra 10.13.3 Build 17D47
By January 2018, Apple was still recovering from the embarrassment of the in 10.13.1, where anyone could unlock "System Preferences" > "Users & Groups" with a blank password. While the emergency patch (Build 17D47) didn't re-introduce the bug, it hardened the Authorization Plugin system further. As an "under-the-hood" release, performance was largely tied
As part of the High Sierra lifecycle, this build supports the following hardware: Late 2009 or newer MacBook Pro/Air: Mid/Late 2010 or newer Mac mini: Mid 2010 or newer iMac: Late 2009 or newer Mac Pro: Mid 2010 or newer By January 2018, Apple was still recovering from
Note: Apple confirmed that no known exploitation of Spectre/Meltdown had occurred on macOS at the time of release, but the patch was proactive.
The primary goal of Build 17D47 was to bolster system stability and resolve specific user-facing issues: