Ask HN: It seems to be impossible to find-replace text in a PDF at scale?

I have a bunch of generated PDF invoices, which all have the same typo, that I'd like to fix.

So far I have tried:

* pdftk via bash script

* qpdf via bash script

* PyPDF2

* pdf-lib via node

In all cases, it appears the PDF content is not in plain text, so the text replacement fails.

Often I'm getting:

> Unsupported contents type: <class 'PyPDF2.generic.TextStringObject'>

I'm surprised it's this hard to do a find-replace inside a PDF. Isn't there a Homebrew util for this?

GPT4 has been having me write a hundred variations of scripts, but not a single one addresses the "this isn't plain text" problem.

How would you go about doing find-replace of a text string in a PDF at scale (on Mac)?