Since v 3.9.5 Smart Checklist add-on stores checklist content in Jira Issue Properties.
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Features support per Smart Checklist add-on storage type
As you see, the main checklist functionality is supported with Issue Properties and right after add-on installation on the Jira instance.
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Understanding of Issue Property and "Checklists" custom field synchronization
Add-on uses our database as first priority storage and then syncs it with "Issue Property" and the "Checklists" custom field(if present).
When a checklist is changed, it is updated everywhere: in our database, in issue property, and in the custom field.
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