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How to bulk copy and paste checklist tasks

Navigate to the checklist of your choice. This can be a new template or an ad-hoc checklist in a Jira issue or Confluence page.
Open the text editor of your choice which has the tasks already listed out. Select your list and copy it.
Paste your copied text into the checklist template or ad-hoc checklist.
If you would like to quickly remove your pasted content, you can press the “undo” button.