I am sorry to hear you have encountered this misbehavior and will be glad to help you sort it out.
Actually, this is a known, for us in Test Studio, issue with the extracted variables in code and data driven elements' find expression - there is also a public item on the topic listed in our feedback portal. Although, the item dates back quite many years ago, the behavior is still the same.
The workaround to overcome this limitation is to set a dummy data source to enable the data driven logic for the test and allow the elements' find logic to be data driven. The easiest way to do this will be to add a local data source in the test. You need to enter data in a single cell of the data table and save the test. Then you will see the dropdown in the element's Edit mode.
Please, note that the extracted variables are not listed in this dropdown and you need to manually type the name in the input field, click on the curly brackets and then the Set button.
I hope that this will help you adjust the test you work on. Do not hesitate to get back to me in case of any further questions on the case.
Thank you for your understanding and cooperation in advance.
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