Merge branch 'set-transient-for-offscreen-windows' into 'gtk-3-24'

GdkWindow: Check for offscreen windows in set_transient_for ()

See merge request GNOME/gtk!6184

gdk/gdkwindow.c

@@ -10542,6 +10542,13 @@ void
 gdk_window_set_transient_for (GdkWindow *window,
 			      GdkWindow *parent)
 {
+  if (!gdk_window_is_offscreen (window) &&
+      parent != NULL &&
+      gdk_window_is_offscreen (parent))
+    {
+      return;
+    }
+
   window->transient_for = parent;
 
   GDK_WINDOW_IMPL_GET_CLASS (window->impl)->set_transient_for (window, parent);

gtk/gtkmenu.c

@@ -5263,6 +5263,24 @@ gtk_menu_position (GtkMenu  *menu,
         }
     }
 
+  if (rect_window != NULL &&
+      GDK_WINDOW_TYPE (rect_window) == GDK_WINDOW_OFFSCREEN)
+    {
+      GdkWindow *effective = gdk_offscreen_window_get_embedder (rect_window);
+
+      if (effective)
+        {
+          double x = rect.x, y = rect.y;
+
+          gdk_window_coords_to_parent (rect_window, x, y, &x, &y);
+
+          rect.x = x;
+          rect.y = y;
+        }
+
+      rect_window = effective;
+    }
+
   if (!rect_window)
     {
       gtk_window_set_unlimited_guessed_size (GTK_WINDOW (priv->toplevel),