menu_configuration.cpp надо строчку добавить
#if DISABLED(SLIM_LCD_MENUS)
// Preheat configurations
MENU_ITEM(submenu, MSG_PREHEAT_1_SETTINGS, menu_preheat_material1_settings);
MENU_ITEM(submenu, MSG_PREHEAT_2_SETTINGS, menu_preheat_material2_settings);
MENU_ITEM(submenu, MSG_PREHEAT_3_SETTINGS, menu_preheat_material3_settings);
#endif