Apple has released macOS Mojave 10.14 beta 4 to developers for testing. The build number is 18A336e.
macOS Mojave introduces a new Dark Mode, Stacks, Group FaceTime, and much more.
In macOS Mojave, a new Dark Mode transforms the desktop with a dramatic new look that puts the focus on user content. The new Stacks feature organizes messy desktops by automatically stacking files into neat groups. Familiar iOS apps, including News, Stocks, Voice Memos and Home, are now available on the Mac for the first time. FaceTime now adds support for group calling, and the Mac App Store gets a full redesign featuring rich editorial content and the addition of apps from top developers, including Microsoft, Adobe and others.
Developers can get the macOS Developer Beta Access Utility from the link below to download the latest macOS 10.14 beta. As new macOS betas become available you will receive a notification and can install them from the Software Updates panel in System Preferences.