Dark Mode for macOS is Leaked via Images. Images can be seen in the dark mode that is most likely added to macOS version 10.14. The images were posted on Twitter by developer Steve Troughton-Smith.
He discovered a video showing the dark mode. macOS already has the option to provide the menu bar and so-called Dock in the operating system with a dark grey colour, but this does not change the colour of menus and backgrounds within apps. The dark mode in the leaked macOS 10.14 images resembles the entire screen.
The leaked video also confirmed that app pages on the Mac App Store could show 10.14 videos from macOS. As a result, macOS users can now see apps running in advance, on top of the static images that can now be shown by developers.
Apple has not officially announced the new features yet. The company will resist its annual WWDC conference on Monday evening Dutch language, on which, among other things, the latest version of macOS will be unveiled. IOS 12 will also be shown during the event.