What objects in the context are not affected by flattening (Notability)?

[jbeuckm]

I need to write a string to the PDF (not visible or metadata) that can be read back later after the PDF is edited with Notability. I tried to embed an image with the data but after the user edits in Notability, the embedded images are gone - I assume because of flattening.

What kind of object could be written to the context that will stay the same after editing/flattening in Notability?

[Hopding]

Looks like you identified hidden fields as a solution in #730, so I'll go ahead and close this for now.

Note also that in addition to adding a field to a page and then hiding it, it should also be possible to simply create a field and set its value without ever adding it to a page in the first place.

[Hopding]

Actually, I'm not sure if hidden fields will necessarily be excluded from a flattening operation, so that may not address this issue. Looks like you've already come across #593 (comment). You could register whatever kind of object you want in the document by using pdfDoc.context.register(...).