Hi
Gordon ,
Thank you for your interest in Syncfusion products.
Can you please provide us more details about what is here mentioned as tabs in the PDF document, does it mean the tab order in moving between the form elements in the PDF form, if so at present we do not support editing the forms in the PDF Viewer. We have included a Feature request report for the implementation of this feature.
Please let us know if you have any concerns.
Thanks,
Suresh
