diff --git a/src/window.cpp b/src/window.cpp
index 2468c50104..390777fae6 100644
--- a/src/window.cpp
+++ b/src/window.cpp
@@ -915,6 +915,7 @@ static uint GetWindowZPriority(const Window *w)
 
 		case WC_SAVELOAD:
 		case WC_GAME_OPTIONS:
+		case WC_CUSTOM_CURRENCY:
 		case WC_NETWORK_WINDOW:
 		case WC_GRF_PARAMETERS:
 		case WC_NEWGRF_TEXTFILE: