- Adds AirPlay 2 multiroom audio support for iTunes and improves the stability and security of your Mac.
- Control your home audio system and AirPlay 2-enabled speakers throughout your house.
- Play music at the same time on multiple AirPlay 2-enabled speakers in your house, all in sync.
Other improvements and fixes
- Fixes an issue that may prevent Photos from recognizing AVCHD media from some cameras.
- Fixes an issue that may prevent Mail users from moving a message from Gmail to another account.
- See Apple Security Updates for detailed information about the security content of this update.
- Two supplemental updates were released in August 2018 to address thermal stability issues with 2018 MacBook Pro models with Touch Bars.
- About the macOS High Sierra 10.13.6 Update at Apple Support (2018-07-09, archived 2018-07-10)