Hi Jerzy,
I must admit that it sound strange, but I don't know the background. So let's stick to your question. :)
I assume that you are using the dictionary as a data source for the fields. In your case I would change this to sql/current database and provide a query similar to:
Select distinct Columnname (taken from the objects tab)
From wfelements
Where wfd_dtypeid = IdOfDictionaryFormType
And ActiveColumnName = 1
I've written this on my mobile so there could be spelling errors. :)
Off topic:
Are you aware of the autocomplete mode and target fields?
https://community.webcon.com/posts/post/form-fields-default-values/80
Maybe your use case is similar to the one mentioned in the article and you can change your approach.
Best regards,
Daniel