After much beta testing, Apple has finally released the macOS 10.13.5 (17F77) to the public. Along with bug fixes and performance improvements, the macOS 10.13.5 update brings Messages in iCloud which rolled out to iOS devices earlier this week.
The update also brings the ‘Ink Cloud’ wallpaper which was previously only offered on the iMac Pro, improved external GPU support, and other minor tweaks.
You can enable Messages in iCloud feature from Messages app settings. It may not be enabled by default after you update your Mac to macOS 10.13.5, so be sure to check for it under Preferences in Messages.
The macOS High Sierra 10.13.5 Update improves the stability, performance, and security of your Mac, and is recommended for all users.
This update adds support for Messages in iCloud, which lets you store messages with their attachments in iCloud and free up space on your Mac. To enable Messages in iCloud, go to Preferences in Messages, click Accounts, then select ”Enable Messages in iCloud.”