10.1.1 Saxon 6.5.2

Saxon is the XSLT processor used in tbook. It is called by tbtolatex, tbtohtml, and tbtodocbk.

1. High Unicode numbers (>65535) cannot be processed in most places. Some people want to use e.g. Fraktur letters in their formulae. The first problem they experience is that the standard MathML2 entity names (e.g. 𝔐) are not defined in tbook. I excluded them because Saxon can't process them in many cases. This is a known Saxon bug. See the Saxon bug tracker for the whole story.