Fixed update of the default menu after changing of the mode.

+ Added check for the output directory for the G-code extport.

src/slic3r/GUI/GUI_App.cpp

@@ -1780,7 +1780,7 @@ void GUI_App::update_mode()
     for (auto tab : tabs_list)
         tab->update_mode();
 
-    plater()->update_object_menu();
+    plater()->update_menus();
     plater()->canvas3D()->update_gizmos_on_off_state();
 }