I'm on Ubuntu 18.04 64-bit
LilyPond 2.19.83 or any other version
For viewing PDF I use evince or FoxitReader.
I've never seen any source-code anywhere
Apart from the cited sentence from the Usage Manual there is no
documentation, no regtest, nothing.
Obviously I've no clue what to do.
It may be that this feature isn't what I want at all, though without
having it working I can't judge.
What I really want Is to print the source-code of my file at the top
of the generated image.
For now I try to modify verbatim-file-markup to be a
markup-list-command and to create other commands to select, delete,
format it as I like.