Preview results is generating an empty array

Hi,
I am trying to review the results when creating a script filed.
It is empty.
Is it a bug or a feature?

Kibana 7.3.2

89%20-%20Remote%20Desktop%20Connection
Thanks!

That means that the scripted field returns no results in the last 10 documents. Can you post the scripted field and a doc example so that we can help you debug?