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We use the term 'Issue in Transition' when we refer to thhe issue for which a workflow condition is checked, for which a workflow validator is examined, of or for which a workflow post function is performed.
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Other workflow modules do not have source and destination, so . So you just define the issue relation, which will apply for that workflow module.
For example Create a Linked Issue will just create a new issue and then connect it with some Issue Relation to the issue in transition.
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