PDF version 1.7 by default?

[Zdenek Wagner]

so 8. 2. 2025 v 0:05 odesílatel Karl Berry <karl at freefriends.org> napsal:
>
> Ulrike tells me the PDF Association is now recommended that the default
> PDF output be version 1.7, and suggests that TeX Live follow suit. Right
> now our formats are set up to output PDF 1.5 by default.
>
> Does anyone know of specific practical compatibility problems that might
> ensue if we switch to 1.7 by default? I know there can be problems "in
> theory". But does anyone know of resulting problems in practice?
>
I only know that this can violate PDF/X but this is the case of 1.5 as
well. In past, I used 1.5 where PDF/X was required and it worked well.
LaTeX should not be a special case, it is just a matter whether PDF
1.7 is accepted by the partners and it does not matter how it was
created. If we say that TeX Live 2025 has PDF 1.7 as the default, it
should be the same for all engines and formats in order to prevent
confusion.

> While I'm here, FYI, Ulrike also says that for LaTeX
>
> > We will default to 2.0 if \DocumentMetadata is used, as this is better
> > when the PDF is tagged
>
> Thanks,
> Karl


Zdeněk Wagner
https://www.zdenek-wagner.eu/