Hi Diane Reese,
At present, we do not have support for “retrieve and modify the custom metadata from the PDF document in flutter PDF library” and we have already logged a feature request for this. We do not have any immediate plans to implement this feature. During the planning stage of each release cycle, we review all open feature requests and determine which features to implement based on various factors, including product vision, technological feasibility, and customer interest. We will notify you when this feature is implemented.
Please follow the feedback link to track the status of the feature,
Regards,
Abinaya E