diff --git a/src/dock_gui.cpp b/src/dock_gui.cpp
--- a/src/dock_gui.cpp
+++ b/src/dock_gui.cpp
@@ -119,8 +119,14 @@ struct BuildDocksToolbarWindow : Window 
 		if (_settings_client.gui.link_terraform_toolbar) DeleteWindowById(WC_SCEN_LAND_GEN, 0, false);
 	}
 
-	void OnInvalidateData(int data = 0)
+	/**
+	 * Some data on this window has become invalid.
+	 * @param data Information about the changed data.
+	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
+	 */
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
 	{
+		if (!gui_scope) return;
 		this->SetWidgetsDisabledState(!CanBuildVehicleInfrastructure(VEH_SHIP),
 			DTW_DEPOT,
 			DTW_STATION,