Editing Square balloons

Elements of notation can be marked and named with the help of a square balloon. The primary purpose of this feature is to explain notation.

<lilypond version="2.24.0">
%% http://lsr.di.unimi.it/LSR/Item?id=423

\new Voice \with { \consists "Balloon_engraver" }
  \relative c''{
   \balloonGrobText #'Stem #'(3 . 4) \markup { "I'm a Stem" }
   a4
   <c, g'-\balloonText #'(-2 . -2) \markup { "I'm a note head" } c>2.
}
</lilypond>

[[Category:Editorial annotations]]
[[Category:Text]]
[[Category:Contexts and engravers]]
[[Category:Really simple]]