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JSU Add-On User (default): The Perform as JSU Add-On User has all the necessary permissions to action all of your JSU post functions. If you don't specify a different option, the transition on the related issue is performed as the JSU app user with its associated permissions. This option is useful for testing, and you can confirm the action in your issue activity.
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Initiating User: The transition on the related issue is performed with the same user who triggered this post function on the origin issue. That user must have the necessary permissions on the related issue. In some restrictive setups, a user might not be allowed to perform the action or might not have permission to view the relevant project.
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