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Click the admin dropdown and choose Atlassian Marketplace.
Click Find new add-ons from the left-hand side of the page.
Locate Download Simple Attachments Downloader for Jira via search.
Click Free Trial to begin a new trial or Buy now to purchase a license for Download Attachments for Jira.Simple Attachments Downloader for Jira
Enter your information and click Generate license when redirected to MyAtlassian.
Click Apply license.