Is the Mac heading to the Dark Side? A new leak suggests that could be the case.

Software programmer Steven Troughton-Smith took to Twitter on Saturday to say he'd come across an internal Apple video that shows the company's Xcode development tool running on Mac OS 10.14. That's the upcoming version of the operating system, expected to be previewed at WWDC 2018, which starts Monday.

Screenshots posted by Troughton-Smith suggest 10.14 may have a full dark mode, which would let you drape the user interface in nightlike tones. Currently in Mac OS, you can go part of the way there, by choosing System Preferences/General/"Use dark menu bar and Dock." But Troughton-Smith's screenshots suggest you may soon be able to take that color preference system wide.

Other intelligence gleaned from the leak? There appears to be an Apple News icon in the dock, which may herald the arrival of a News desktop app for the Mac. And 9to5Mac, which earlier reported on Troughton-Smith's tweet, said that sand dune wallpaper visible behind the active windows in the OS suggests 10.14 might be called "Mojave."

Apple didn't respond to a request for comment.

Guess we'll just have to wait and see. In the meantime, you can fill up on more rumors here: "WWDC 2018: What to expect from iOS 12, MacOS 10.14 and more."

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