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Open your Jira project and select Project settings from the left sidebar.
When the sidebar refreshes, go to Issues > Collectors.
Select Add issue collector, fill in the required information, and select the Custom option (see Trigger section: Trigger style).
Copy 
Select the Submit button and copy the generated code that appears on the next page.
Paste it into the Spacecraft app and customize it as needed in the Spacecraft app.
See also
How to use the issue collector.
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