diff --git a/src/xdp-app-info-flatpak.c b/src/xdp-app-info-flatpak.c
index bae0cf3ae..66a24d84c 100644
--- a/src/xdp-app-info-flatpak.c
+++ b/src/xdp-app-info-flatpak.c
@@ -509,6 +509,8 @@ xdp_app_info_flatpak_class_init (XdpAppInfoFlatpakClass *klass)
     xdp_app_info_flatpak_validate_autostart;
   app_info_class->validate_dynamic_launcher =
     xdp_app_info_flatpak_validate_dynamic_launcher;
+  app_info_class->is_valid_sub_app_id =
+    xdp_app_info_flatpak_is_valid_sub_app_id;
 }
 
 static void
diff --git a/src/xdp-app-info-host.c b/src/xdp-app-info-host.c
index 9b7a1f80d..6ca0b7e9b 100644
--- a/src/xdp-app-info-host.c
+++ b/src/xdp-app-info-host.c
@@ -93,6 +93,8 @@ xdp_app_info_host_class_init (XdpAppInfoHostClass *klass)
     xdp_app_info_host_validate_autostart;
   app_info_class->validate_dynamic_launcher =
     xdp_app_info_host_validate_dynamic_launcher;
+  app_info_class->is_valid_sub_app_id =
+    xdp_app_info_host_is_valid_sub_app_id;
 }
 
 static void