diff --git a/src/misc_gui.cpp b/src/misc_gui.cpp
--- a/src/misc_gui.cpp
+++ b/src/misc_gui.cpp
@@ -1003,7 +1003,7 @@ struct QueryStringWindow : public Window
 		}
 	}
 
-	virtual void DrawWidget(const Rect &r, int widget) const
+	void DrawWidget(const Rect &r, int widget) const override
 	{
 		if (widget != WID_QS_WARNING) return;