An up to date Apple Support record hasthe function Back to My Mac is being discontinued in macOS Mojave (push notifications had been additionally despatched to customers as smartly):
Back to My Mac might not be to be had on macOS Mojave. You can get able now by means of studying about possible choices for document get right of entry to, display screen sharing, and far flung desktop get right of entry to.
Back to My Mac used to be introduced with Mac OS X Leopard (10.5) as a MobileMe provider, however sooner or later moved over to iCloud with OS X Lion. The function, in accordance to Apple, “permits you to arrange a community of Mac computer systems that you’ll be able to get right of entry to remotely.”
Alternatives to Back to My Mac? Apple says to use iCloud Drive to get right of entry to information throughout gadgets, or use display screen sharing to view and keep watch over your different Mac. Another method is to use Apple Remote Desktop, which shall we customers run apps and information on different Macs.
Apple is anticipated to unencumber macOS Mojave 10.14 this autumn, along iOS 12, tvOS 12 and watchOS 5.