The new macOS High Sierra 10.13.4 beta can be downloaded from the Apple Developer Center or through the Software Update mechanism in the Mac App Store with the proper profile installed.
macOS High Sierra 10.13.4 includes bug fixes and performance improvements for issues that weren't addressed in macOS High Sierra 10.13.3.
The update offers support for some features that are available in iOS 11.3, like Messages on iCloud, which uploads all of your iMessages to the cloud. It will also support Business Chat, a feature coming when iOS 11.3 and macOS 10.13.4 are released to the public, and it includes support for eGPUs. Apple released release notes for macOS High Sierra beta 6 in certain countries, providing details on what's included in the update. The notes are below:
- Adds support for Business Chat in Messages in the U.S. and CanadaThe macOS 10.13.4 update also brings the smoke cloud wallpaper that was previously only available on the iMac Pro and it introduces a warning when opening up a 32-bit app as part of an effort to phase them out.
- Adds support for external graphics processors (eGPU)
- Fixes a graphical corruption issue affecting some iMac Pro apps
- Adds a keyboard shortcut for moving to the rightmost open tab in Safari by pressing Command +9
- Adds a feature for sorting Safari bookmarks by name or URL
- Fixes a bug that could prevent links from appearing in Messages
- Improves protection o confidential data by filling usernames and password fields in Safari only when selected
- Displays new warnings in the Safari Smart Search Field when interacting with forms that require credit card data or passwords on unencrypted web pages
- Displays more information on how personal data is used by certain features
In the future, Apple plans to phase out 32-bit Mac apps, just like it did with 32-bit iOS apps. Apple says macOS High Sierra is the last version of macOS that will support 32-bit apps without compromises.
We're nearing the end of the macOS High Sierra beta testing period and a release could come any day now.