diff --git a/src/station_gui.cpp b/src/station_gui.cpp
--- a/src/station_gui.cpp
+++ b/src/station_gui.cpp
@@ -23,6 +23,7 @@
 #include "window_func.h"
 #include "viewport_func.h"
 #include "gfx_func.h"
+#include "widgets/dropdown_func.h"
 
 #include "table/strings.h"
 #include "table/sprites.h"