diff --git a/src/moongreet/greeter.py b/src/moongreet/greeter.py
index 8178a59..64c724d 100644
--- a/src/moongreet/greeter.py
+++ b/src/moongreet/greeter.py
@@ -74,6 +74,7 @@ class GreeterWindow(Gtk.ApplicationWindow):
         # Defer initial user selection until the window is realized,
         # so get_color() returns the actual theme foreground for SVG tinting
         self.connect("realize", self._on_realize)
+        self.connect("unrealize", self._on_unrealize)
 
     def _on_realize(self, widget: Gtk.Widget) -> None:
         """Called when the window is realized — select initial user.
@@ -84,12 +85,11 @@ class GreeterWindow(Gtk.ApplicationWindow):
         """
         GLib.idle_add(self._select_initial_user)
 
-    def do_unrealize(self) -> None:
+    def _on_unrealize(self, widget: Gtk.Widget) -> None:
         """Clean up resources when the window is unrealized."""
         if self._wallpaper_ctx is not None:
             self._wallpaper_ctx.__exit__(None, None, None)
             self._wallpaper_ctx = None
-        super().do_unrealize()
 
     def _build_ui(self) -> None:
         """Build the complete greeter UI layout."""