The following Table displays the all the accepted Template Extensions and the supported Outputs Formats, as well as the expected results for each combination:
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PDF/A is an ISO-standardized version of PDF specialized for use in the archiving and long-term preservation of electronic documents. You can read more about this standard here.
Xporter for Jira supports this format on V5.3.0 and higher.
PDF/A and Attachments
Xporter for Jira supports exporting issues with attachments in PDF/A standard.