diff --git a/runtime/include/psx_menu_host.h b/runtime/include/psx_menu_host.h
index d85dfff3..8dfb7595 100644
--- a/runtime/include/psx_menu_host.h
+++ b/runtime/include/psx_menu_host.h
@@ -25,6 +25,8 @@ extern "C" {
 #endif
 
 #define PSX_MENU_ABI_VERSION 1
+/* PsxMenuHost.default_selection is present (appended, ABI-compatible). */
+#define PSX_MENU_HOST_HAS_DEFAULT_SELECTION 1
 
 /* request_exit */
 enum {