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When the post function is performed, it will trigger the transition with that particular id (51 in the example above) on the linked issues. If one of the linked issues uses a different workflow, but has a transition with the same id, that transition will be triggered. The name of the transition you see in the configuration screen actually does not really matter. What matters is only the id. If you want to trigger only the transition on one workflows in that case, use the JQL scope and select the issues to transition with a query similar to issue in linkedIssues({issue.key}) and project = “PR Next Project”.
If the transition with that id is not available on the linked issue (probably because it is in a different status) nothing will happen. Also no comment or fields are copied, no resolution is set.
It is important to keep this in mind and design your workflows accordingly to prevent them to become sort of 'out of sync'. You might also use several 'Linked Transition' post functions in the same transition, each calling a different target transition, to match possible different statuses of the linked issue.
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