The case is selected based on the value going to the selector terminal so I am confused what you mean by "select" at edit time. Do you want to "show" the code of a certain case? What do you mean by "frame"? What is the "index" of a case? Since cases can be reordered without changing the code logic, it is not clear what you actually want here. Could you clarify?
I don't think there is a need for this because the Case structure does not depend at all on the index. The only structure that does is the stacked sequence structure, and there is a strong push for people to not use that.
If this were implemented, and then someone went in and rearranged your cases, then any code that relies on your index would break.
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