Preview form filling

Preview does not understand Adobe's Acrobat JavaScript syntax, and some PDFs may have directives in them to use Acrobat plug-ins as helpers in viewing the PDF. Preview completely ignores all of the preceding. Any form with associated AcroJS will get the same treatment.

In July 2021, I posted an AcroJS example that set a expiration date on a PDF using what was then PDFpenPro, and after that product acquisition, it is now named Nitro PDF Editor. Adobe Acrobat Reader DC recognizes this document as expired, pops the dialog, and then exits the PDF. Apple's Preview just opens it without any message.

Pierre Nobs wrote:

The button "Form Filling" remains grey, how to activate?

It is possible the "form Filling " is not available for the PDF(?)

I would try a true PDF editor, there are many, here are a few examples:

Adobe Acrobat DC

https://get.adobe.com/reader/

PDFpen

https://pdfpen.com/pdfpen/

pdfExpert

https://pdfexpert.com/

Master PDF Editor

https://code-industry.net/masterpdfeditor/?-about&ver=5832

Pierre Nobs wrote:

Thanks @leroydouglas. As I'm subscribed to Adobe Acrobat Pro, I have no problems filling in forms, but I thought that Preview offers an easy, faster alternative. (?)

Preview.app is a multi-functional application that has its place—however it is not a true PDF editor. Full stop.

You do not always have control of permission r/w capabilities of a PDF depending on who & how the PDF was authored. Nothing new here.

I would use what works.

You can submit your Apple Feedback here:  http://www.apple.com/feedback