diff --git a/lib/gitlab/ci/config/external/mapper/verifier.rb b/lib/gitlab/ci/config/external/mapper/verifier.rb
index 83ef58bb46f8c9dd3f8d4e3df9c3816233c4a6ff..2982b0efb6c1f3ba2c670e6a398a7e02cfb8dfa8 100644
--- a/lib/gitlab/ci/config/external/mapper/verifier.rb
+++ b/lib/gitlab/ci/config/external/mapper/verifier.rb
@@ -28,7 +28,7 @@ def process_without_instrumentation(files)
                 file.validate_content! if file.valid?
                 file.load_and_validate_expanded_hash! if file.valid?
 
-                if ::Feature.enabled?(:ci_includes_count_duplicates, context.project)
+                if context.expandset.is_a?(Array) # To be removed when FF 'ci_includes_count_duplicates' is removed
                   context.expandset << file
                 else
                   context.expandset.add(file)