Microsoft is working on a new design language for Windows 10 codenamed Project NEON

[Windows Central]

Microsoft has made several adjustments to its design language over the last few years, starting with Windows 8 and evolving into what we now know as "Microsoft Design Language 2" or MDL2 in Windows 10. With MDL2 being the current design language used throughout Windows 10, Microsoft has plans to begin using a much more streamlined design language with Redstone 3, codenamed Project NEON.

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