gtkplug/gtksocket is deprecated in gtk3. you might try xembed for embedding system tray apps, but it won’t work natively on windows. for managedshell, consider hosting it in a gtk drawing area using a native windows hwnd container (like using gtk's gdk_win32_window_get_impl_hwnd). another option is to use a wpf/gtk hybrid with x11 forwarding if cross-platform matters.