diff --git a/src/virt-viewer-display-spice.c b/src/virt-viewer-display-spice.c
index 6a7f4a9..fb1f789 100644
--- a/src/virt-viewer-display-spice.c
+++ b/src/virt-viewer-display-spice.c
@@ -201,7 +201,9 @@ virt_viewer_display_spice_size_allocate(VirtViewerDisplaySpice *self,
     if (self->priv->auto_resize == AUTO_RESIZE_FULLSCREEN) {
         GdkRectangle monitor;
         GdkScreen *screen = gtk_widget_get_screen(GTK_WIDGET(self));
-        int n = gdk_screen_get_monitor_at_window(screen,
+        int n = virt_viewer_display_get_monitor(VIRT_VIEWER_DISPLAY(self));
+        if (n == -1)
+            n = gdk_screen_get_monitor_at_window(screen,
                                      gtk_widget_get_window(GTK_WIDGET(self)));
         gdk_screen_get_monitor_geometry(screen, n, &monitor);
         disable_display_position = FALSE;