I see no new options with man pdftex or pdftex --help .
with Adobe’s Preflight for PDF/A-1b.
This is pdfTeX, Version 3.14159265-2.6-1.40.19 (MiKTeX 2.9.6930 64-bit) (preloaded format=pdflatex 2019.1.11) 23 JAN 2019 16:46
but there is no error when I build the analogous PDF with:
This is pdfTeX, Version 3.14159265-2.6-1.40.19 (TeX Live 2018) (preloaded format=pdflatex 2018.12.24) 25 JAN 2019 17:16
The attached image shows that the CharSet is included on a Mac, using MacTeX,
but not with MikTeX, even though the version of pdfTeX seems to be identical.
The only explanation that I can think of is that a primitive or option is being used
in one case, but not the other.
Can someone please shed some light on what may be causing this difference?
Could it really be connected with the LaTeX format version?
For me, tlmgr update --list
doesn’t list anything needing an update that is obviously relevant.