Right now, if you go to the following page and click "Prev", it'll send you
to the middle of the previous chapter:
https://www.postgresql.org/docs/devel/bgworker.html
My research indicates that this might caused by a bug in libxml2, but
regardless, a minimal fix is to change the link generation code to use
[position()=last()] instead of [last()] in the predicate on the union of
reverse axes. Patch attached.
--
nathan
