diff --git a/src/engine_gui.cpp b/src/engine_gui.cpp
--- a/src/engine_gui.cpp
+++ b/src/engine_gui.cpp
@@ -144,7 +144,7 @@ struct EnginePreviewWindow : Window {
 };
 
 static WindowDesc _engine_preview_desc(
-	WDP_CENTER, "engine_preview", 0, 0,
+	WDP_CENTER, nullptr, 0, 0,
 	WC_ENGINE_PREVIEW, WC_NONE,
 	WDF_CONSTRUCTION,
 	_nested_engine_preview_widgets, lengthof(_nested_engine_preview_widgets)