According [http://standards.freedesktop.org/basedir-spec/latest/ base directories from freedesktop], the working paths should could be:

* devhelp ''~/.local/share $XDG_DATA_DIRS/devhelp/books/gramps/gramps.devhelp'' ''/usr/local/share/devhelp/books/gramps/gramps.devhelp'' * gtk-doc ''/usr/share/gtk-doc/html/gramps/gramps.devhelp''