Every software app needs some updates to its user interface. Thus with the Windows 10 Settings app. Along with Windows 10 Insiders Preview Build 17063, Microsoft changed the look & feel of the Settings app with Acrylic material effect.
If you are a Windows Insider, and in the Fast Ring, do not forget to checkout this build. It has bunch of changes and fixes for you to explore.
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The fluent design is now part of the Windows 10 Settings app. Microsoft redesigned the app to have an Acrylic material effect on that to have a consistent look & feel across the system. The new settings homepage includes a design that now has smaller icons with their titles aligned to the right. It also changed the shape of each tile to have a rectangular look instead of square. Also, the existing gear icon has been replaced with a new home icon with the shape of a house.
Not a Windows Insider? Or, didn't get the time to install/explore the build? Not to worry! Here's a small video demonstration for you: