Two days ago I've updated my openSUSE box, which now comes with gs 9.56.1 – previously, I had gs 9.54.0. This new gs version uses a brand-new PDF engine written in C, replacing the old one written in PostScript.
Building the LilyPond documentation I wondered why the new output file size of `notation.pdf` is only 75% of the old size. After some checks I found out that all links are gone. So, a heads-up: gs 9.56.0 and 9.56.1 are buggy! According to https://bugs.ghostscript.com/show_bug.cgi?id=705565 this has been fixed meanwhile, but I have no idea when 9.56.2 gets released. In case you are forced to use 9.56.1, add `-dNEWPDF=false` to the gs command line options (in file `Documentation/GNUmakefile`) to make gs use the old PDF engine, which produces good results. Werner
