Window / AppWindow mapping (WinUI 3 ↔ QWinUI3)¶

WinUI 3	QWinUI3
`Window` + `AppWindow`	`StandardWindow` (`DialogWindow` / `ToolWindow` / `CompactOverlayWindow`)
`AppWindow.Presenter` Overlapped / FullScreen / CompactOverlay	`WindowHelper.Presenter*` + `StandardWindow.presenter`
`SystemBackdrop` Mica / Acrylic	`WindowHelper.Backdrop*` + `StandardWindow.backdrop`
`AppWindowTitleBar`	`PlatformTitleBar` + `CaptionButton`
`TitleBar` (LeftHeader / Icon / Title / Subtitle / Content / RightHeader / Back / PaneToggle)	`QWinUI3.Extras.TitleBar`
`ExtendsContentIntoTitleBar`	`StandardWindow.extendsContentIntoTitleBar` (custom frame)
`PreferredHeightOption` Standard / Tall	`WindowHelper.TitleBarHeight*`
ContentDialog (in-app modal)	`ContentDialog` + `ContentDialogQueue` (not a top-level HWND)
Dialog / Tool / CompactOverlay app windows	`DialogShellWindow` / `ToolShellWindow` / `CompactOverlayShellWindow`
System reduce animations / high contrast	`WindowHelper.systemReducedMotion` / `systemHighContrast` → `Theme.*`

Composition:

StandardWindow
  └── header: PlatformTitleBar          // caption buttons + hit-test
        └── TitleBar { embedded: true } // WinUI TitleBar content

See also window-transparency-dwm.md for Solid vs Mica/Acrylic gallery policy.