diff --git a/cluster/manifests/01-platformcredentialsset/customresourcedefinition.yaml b/cluster/manifests/01-platformcredentialsset/customresourcedefinition.yaml
index fe121346e6..fbc3ce9895 100644
--- a/cluster/manifests/01-platformcredentialsset/customresourcedefinition.yaml
+++ b/cluster/manifests/01-platformcredentialsset/customresourcedefinition.yaml
@@ -5,6 +5,9 @@ kind: CustomResourceDefinition
 metadata:
   name: platformcredentialssets.zalando.org
 spec:
+  # {{ if eq .Cluster.Environment "test" }}
+  preserveUnknownFields: false
+  # {{ end }}
   scope: Namespaced
   group: zalando.org
   names: