On 16/05/2018 23:57, Karl Berry wrote:
The only pdftex 1.50 info I know about is from here: http://tug.org/svn/pdftex/branches/qstex/README.qstex which are actually some changes over 1.50, but it's all I've got.
Doing a diff against the qstex branch pdftex.web from the "stable" (which I really must move back to trunk) branch, I see stuff relating to pdf layers and not much else in terms of primitives.
I think at this remove it's likely not that worth worry about. If one were using semantic versioning, adding a new primitive would bump the minor version (so something like 1.41.0). However, that's not how pdfTeX versions work: the 'step' is .10 anyway, and various primitives have been added between 1.40.0 and the current release. So I was imagining that the pattern would continue. Joseph