In order to build the Kawa documentation (with sources for the invoke
branch from the Gitlab repo) following the instructions at

  https://www.gnu.org/software/kawa/Source-distribution.html

I found that I needed to edit the URL for chunkfast.xsl in
doc/style/kawa.xsl.  (Otherwise I got errors about failing to load
external entity style/chunkfast.xsl.)  I have included a patch below for
completeness, even though the change it is quite trivial.

The Debian docs seem to suggest the change should be generally
applicable but I am not sure.  Even if the patch doesn't make sense in
general, this message may help others with a setup similar to mine,
which is Debian 8 (Jessie).  I got the idea for the replacement URL from
/usr/share/doc/docbook-xsl/README.Debian.gz file of the docbook-xsl
package on Debian.

With this change, I was able to build the HTML documentation and the
resulting HTML pages look like the ones on the gnu.org Kawa site, with
the exception that the table of contents in the left pane are missing,
and in their place is a link to the table of contents.  (I didn't
investigate that issue further yet.)

Regards,

-chaw