NC11 + OCR 2.0.0: Can't OCR a pdf?

I’m on NC 11.0.1 with OCR 2.0.0

OCRing a PNG works well, but when doing it with a PDF, it won’t work

OCR Verarbeitung für %n Dateien fehlgeschlagen.

In /ncdata/nextcloud.log nothing to see.

What is wrong?
Thank you.

I think this might be a good topic for the documentation and this forum as well as it should be the same problem as I recognized a few times ago:

Unfortunately yet, the nextcloud log will not store any OCRWorker related error messages. But I will work on this soon.

The ocrmypdf command actually has many dependencies which get updated from time to time via package managers like apt-get or apt. During the last ghostscript update the ocrmypdf command broke and they had to update it.

So I guess an upgrade of the package ocrmypdf should be the solution for this.
As I do not know how one has installed the ocrmypdf package (there are different ways to do it) I will just give an example for the python pip3 managed package:

pip3 install ocrmypdf --upgrade

Hint: you might install it with sudo (if you have it globally available).