Microsoft has quietly updated its Mica “material” for Windows 11 with a more colorful new variant called Mica Alt.
“Mica is an opaque, dynamic material that incorporates theme and desktop wallpaper to paint the background of long-lived windows such as apps and settings,” the Microsoft Docs website explains. “Mica Alt is a variant of Mica, with stronger tinting of the user’s desktop background color. You can apply Mica Alt to your app’s backdrop to provide a deeper visual hierarchy than Mica, especially when creating an app with a tabbed title bar.”
To demonstrate the difference between the two, Microsoft provides two screenshots, both of which show how the desktop wallpaper—which is not shown separately—bleeds through the translucent Mica and Mica Alt materials.
Not sure what a “material” is? According to Microsoft, “materials are visual effects applied to [user experience; really user interface] surfaces that resemble real-life artifacts. Windows 11 uses two primary types of materials: occluding and transparent. Occluding materials, like Acrylic and Mica, are used as base layers beneath interactive UI controls. Transparent materials such as Smoke are used to highlight immersive surfaces.”
Mica was added as a new foundation layer for apps in Windows 11 and it supports light and dark modes and active and inactive states to indicate whether the app window it is being used in has the focus. But the issue with Mica, I guess, is that it can be a bit subtle. So Mica Alt amps up the translucency, allowing the colors in the other windows or background behind the app window to seep through a bit more clearly.
Where Mica is available in both Universal Windows Platform (UWP) and Windows App SDK 1.1+ apps, Mica Alt is only supported by apps based on Windows App SDK 1.1 and higher. Because, as you know, UWP is dead.