Yes, so once the user has saved a questionnaire they’re then able to edit the list of questions to add dependencies between questions.
if(!isset($_GET['post'])) return array(); so that the code wouldn’t try running if the post didn’t have an ID (ie. when it’s a new post – since then there wouldn’t be any custom fields to find, since the post would have never been saved).
Also, to elaborate on what happens, as soon the edit page gets to the repeater field containing the select the code breaks and no more PHP appears to be processed. There are no errors in the log, however.
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