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Save the query as a filter button actives after you perform a search.

Read more about Extended search filters.

JQL Functions

Extended search functions are invoked just like standard JQL functions. They are autocompleted after you start typing issue in…

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issue in childrenOfIssuesInQueryRecursive("project='ACME' and type=Initiative") finds all epics, stories and subtasks in initiatives in project ACME.
issue in childrenOfIssuesInQuerychildrenOfIssuesInQueryRecursive("assignee=currentUser() and type=Initiative", 2) finds epics and stories of all of my epics and skips the subtasks.

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