> I want to use emoji within markup, and I can see in the output log > that Lilypond can't find a character in its default emoji font > (Symbola). I can't figure out how to override the default font.
LilyPond does *not* have a default emoji font! It is Pango and FontConfig which choose the font. Emojis are an especially nasty thing to select. Or to be more precise, you actually can't select them at all within LilyPond, since any setting of a font for an Emoji character is completely ignored. This is due to a Pango problem: https://gitlab.gnome.org/GNOME/pango/-/issues/289 It is necessary to modify the FontConfig setup files (usually in `/etc/fonts/conf.d` or something similarly named) to enforce a certain Emoji font. BTW, I can reproduce your problem, and it is due to `Symbola.ttf` being buggy: (Almost) all of its glyph names are empty – this is technically valid[*] but doesn't work for us: Contrary to many applications, LilyPond selects a glyph by its name if such a name is available. Since this font effectively lies to the application, i.e., providing incorrect glyph names, it fails. Fortunately, it's easy to fix: https://gitlab.com/lilypond/lilypond/-/merge_requests/2235 Werner [*] For TrueType fonts it is normally expected to access glyphs by character code only; glyph names are considered a bonus information.