Apple has released macOS Mojave 10.14.3 beta 4 to developers for testing. The build number is 18D39a.
It’s likely that this build only contains bug fixes and minor improvements but we’ll let you know if any new features are discovered.
Developers can download the macOS Developer Beta Access Utility from the link below to get 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.