I wasn’t up to tackling the lilypond scripts, so I sent the test css
page url to a bunch of people, and put favicons on both laymusic and
brs.
The way I found to get a favicon was to use display to generate a
square image of the right size, and then use png2ico to get the icon.
I gave it both 16×16 and 32×32 icons. The serpent is OK, but the
recorder is only recognizable if you already know what it is.
LayMusic.org 