It’s download time for developers because macOS Mojave 10.14.1 Developer Beta 5 is out. So far it looks like the latest beta focuses on bug fixes and performance improvements.
Earlier macOS Mojave 10.14.1 developer betas brought back Group FaceTime support, which Apple promised is coming in a official release before the end of the year.
macOS Mojave introduced a system-wide Dark Mode, Stacks Desktop file organization, Quick Actions in Finder windows, enhanced screenshot and recording with built-in markup and editing, Continuity for grabbing and editing photos you snap on your iPhone, and more.
macOS Mojave is a free upgrade. It supports the 2015 and later MacBook, mid 2012 and later MacBook Air, mid 2012 and newer MacBook Pro, 2012 and later Mac mini and iMac, iMac Pro, and 2013 Mac Pro.