Need more details on XFDF pdf-info element

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Please give a brief summary of your issue:
When I generate XFDF out of a PDF file with forms fields and annotations added via PDFTron sdk, I see pdf-info element in the xml that contains child elements like , . I need more info on these elements to understand them better. Do you have a SFDF specification which explains these pdf-info elements?

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The pdf-info section is proprietary/internal values only useful to PDFTron products. The XFDF overall is still valid and can be processed by other vendors.

Why is understanding the pdf-info section important for you?
What exact issue are you trying to resolve?

We are building a solution where we require to save the XFDF info at our end so that it can be loaded on demand later. I wanted to understand the pdf elements inside pdf-info. If you could provide some documentation on that it will help.

require to save the XFDF info

Can you just save it as is then? XFDF is XML, which is just a string. No need to actually understand what the internals represent.

If I want to import the XFDF generated by PDFTron with just form field information in another PDF vendor, I dont see form fields in the imported document. But if the same document has annotations, then those annotations gets imported.
As you store form field coordinates inside pdf-info which is proprietary, how this XFDF import with just form field will work on other vendors?

It seems XFDF import with form field (without values) wont work as per XFDF specification. So if ever I have to recreate form field onto a document using another vendor, should I keep an XFDF with just annotations as well?