MacOS 10.13.6

macOS 10.13.6 was an update to macOS 10.13 (High Sierra) released on August 12, 2018.

This update:

 * 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.