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Prevent editing of form field data by flattening PDFs in Adobe Acrobat #

Adobe's 8-step guide on How to flatten a PDF file ends with the instruction to "Print document"; sadly, this feature is missing in the macOS version:

• Printing to PDF missing: "The Mac OS dropped the ability to print directly to a PDF several versions ago."

• Print to PDF: "The Adobe PDF printer is not available on Mac."

Here's a 3-step alternative:

1. Tools → Print Production → Preflight (or use the keyboard shortcut Cmd+Shift+X to save a few clicks)

2. In PDF Fixups, double-click Flatten annotations and form fields

3. Save the new PDF when prompted

and similarly-concise console approach:

1. Press Cmd+J to open the JavaScript Debugger console

2. Enter this.flattenPages(); and press Cmd+Return

3. Save the PDF as desired

Notes

• this.flattenPages(); applies to the current PDF. To flatten all open PDFs, use Thom Parker's script: app.activeDocs.forEach(oDoc=>oDoc.flattenPages());

  • Both commands generally display "undefined" when run, since the flattenPages() method does not produce any return value.

  • However, you might encounter the error "NotAllowedError: Security settings prevent access to this property or method" for protected documents; check File → Properties → Security → Changing the Document.

    • One solution for some PDFs is to first save a copy (File → Save a Copy…) and then make edits to the new file.

• Tested in Adobe Acrobat Pro 2024

• Sanity-preserver: View → Disable new Acrobat

/mac | Oct 18, 2024

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