Where to find Epic Clone?
When you clone an issue in Jira Cloud using Epic Clone, a dialog will pop up allowing you to configure the cloned issue and its child issues. This guide highlights the location of Epic Clone within a Jira issue. Let's consider cloning this issue using Epic Clone:
It includes 3 child issues and 2 linked issues. Child Issue 2 has 3 sub-tasks. By clicking on the three dots → Clone with child issues, you can open the clone configuration dialog.
Please proceed on this page where it is explained what you can do when cloning an issue with Epic Clone.