[texhax] Bad effect when using xetex together with color

[Philip Taylor]

Ulrike Fischer wrote:
> Am Thu, 16 Aug 2018 18:30:57 +0100 schrieb Philip Taylor:
>
>>> color sets \pdfpagewidth and \pdfpageheight
>  
>> This is undoubtedly a very naïve question, but why, might one ask ?
> Do you mean why they are set or why color sets them?

Why "color.sty" sets them.  Surely pdfpagewidth/height have nothing to do with whether or not one wants to use colour — I set them as a matter of course in all my Plain XeTeX source files, and LaTeX users would surely expect them to be set by (e.g.,) "geometry.sty" or by TeX Live based on installation page-size preferences rather than in a file that, to all intents and purposes, appears to exist solely to support the use of colour.

>
> pdf pages sizes should be set nowadays and users shouldn't have to
> worry about which special to use or which variable to adjust to get
> the correct pdf page size. 

Agreed for LaTeX users (not for Plain).

> As the needed settings are engine specific it must be done in engine
> driver files. As color/graphics are used almost always their driver
> files are not a bad place for this. 

Well, with respect, here I disagree.  Argument against adduced above.
** Phil.