EOL marker shall be immediately followed by a %

[williamdes]

I am trying to pass the PDF checks to be able to do Factur-x checks: https://github.com/akretion/factur-x

You can use Vera PDF to check.

https://github.com/veraPDF/veraPDF-validation-profiles/wiki/PDFA-Part-1-rules#rule-612-2

From: https://services.fnfe-mpe.org/

Spec. ISO_19005_3 clause 6.1.2 test 2
PDF/A-3 error
The a forementioned EOL marker shall be immediately followed by a % (25h) character followed by at least four bytes, each of whose encoded byte values shall have a decimal value greater than 127
Level: CosDocument
Context: root