diff --git a/lib/config/config_settings.h b/lib/config/config_settings.h
index 1a0ebf70d..6db9cda68 100644
--- a/lib/config/config_settings.h
+++ b/lib/config/config_settings.h
@@ -823,7 +823,7 @@ cfg_array(global_thin_check_options_CFG, "thin_check_options", global_CFG_SECTIO
 cfg_array(global_thin_repair_options_CFG, "thin_repair_options", global_CFG_SECTION, CFG_DEFAULT_UNDEFINED, CFG_TYPE_STRING, "#S" DEFAULT_THIN_REPAIR_OPTIONS, vsn(2, 2, 100), NULL,
 	"String of options passed to the thin_repair command.\n")
 
-cfg_array(global_thin_disabled_features_CFG, "thin_disabled_features", global_CFG_SECTION, CFG_ALLOW_EMPTY, CFG_TYPE_STRING, NULL, vsn(2, 2, 99), NULL,
+cfg_array(global_thin_disabled_features_CFG, "thin_disabled_features", global_CFG_SECTION, CFG_DEFAULT_UNDEFINED | CFG_ALLOW_EMPTY, CFG_TYPE_STRING, NULL, vsn(2, 2, 99), NULL,
 	"Features to not use in the thin driver.\n"
 	"This can be helpful for testing, or to avoid\n"
 	"using a feature that is causing problems.\n"