A Flutter window whose background is a translucent material, set with Window.setVisualEffect.

• One chip per VisualEffect. The ones Window.isVisualEffectSupported rules out here are greyed out: Mica needs Windows 11 22H2, Linux has none at all.
• The material only shows where the app paints nothing. The shared Host of the examples paints the theme's canvas under everything, so this one is its own WidgetsApp with the same DazzUI theme over it and no background: it paints the canvas only while there is no effect, and leaves the window below the panel bare.
• The controls (DazzUI chips and a switch) keep a card of their own: a material takes its colour from whatever happens to be behind the window, so text laid straight on it is readable over a pale desktop and lost over a dark one.
• The material runs to the top edge of the window. On macOS that takes setContentUnderTitleBar(true), which makes the title bar a transparent overlay with the window buttons still on it; on Windows 11 the system backdrop covers the caption by itself, and on Windows 10 nothing can make it.
• The "Backdrop" switch puts a plain red window behind this one, which makes it obvious which materials blur the windows behind (Blur, Acrylic, Hud, Popover, Menu) and which only take their tint from the desktop picture (Mica).

flutter run -d macos   # or windows, linux

The real-desktop test of this example lives in the workspace repository: tools/gui/flutter_visual_effect_test.py (macOS) and .ps1 (Windows). It starts the example with VISUAL_EFFECT_AUTOPLAY=1, which makes it show the backdrop and walk through the effects by itself.