Multi-window is the oldest item on the Flutter desktop wishlist. A desktop app that cannot open a second window is not really a desktop app — no detached inspector, no tear-off panel, no floating tool palette, no proper context menu that escapes the main window’s bounds. Flutter 3.41 shipped experimental multi-window APIs for desktop. Flutter 3.47 fills in a large amount of the plumbing underneath them. What it does not do is make them stable, and being clear about that distinction will save you a painful quarter. What actually landed in 3.47 The desktop work in this release is mostly engine-level, and it is substantial: Popup windows. Win32 and Linux both got popup window implementations. This is the foundation for menus, tooltips, and dropdowns that render outside the parent window’s bounds — a category of UI that Flutter desktop has faked with overlays until now. Sized-to-content windows. Regular and dialog windows can now size themselves to their content on Win32, and the de...