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Select an epic you want to clone in your Jira instance. For example, consider an epic with four associated issues (two of which are from a different project) as displayed in the following image:
In the top-right corner, select Actions > Clone Plus option or select theClone Plus quick-add button in any issue.
On the Clone Plus for Jira page, select the values as shown in the below image:
Click Clone.
On the Create issue page, select values for all the issue fields as required.
Click Create.
A successful issue creation message is displayed and the parent epic is now cloned to a new epic with all the child issues cloned.