%% Updating this snippet with convert-ly to 2.25. returns:
%%
%% "Not smart enough to convert music following \fine.
%%
%% Warning: \fine no longer enforces the end of the music.  If your piece
%% has music following \fine that you want to exclude when it is
%% unfolded, use \volta to exclude it.
%% Please refer to the manual for details, and update manually."
%%
%% Alas, the use of \fine here is not problematic here --harm

{
  \relative c'' {
    c4 c c c c c c c c c c c
    \repeat segno 2 {
      c4 c c c c c c c
      \alternative {
        \volta 1 {
          c4 c c c c c c c c c c c
          % If you don't use \break at Coda, use \noBreak here
          % and after \bar "" below.
          \noBreak
          \section % double bar line
          \cadenzaOn % pause bar count
          \stopStaff % remove staff lines
          % Increasing the unfold counter will expand the staff-free space
          \repeat unfold 6 {
            s1
            \bar ""
          }
          % Place JumpScript where the staff would normally be.
          \once \override Score.JumpScript.outside-staff-priority = ##f
          \once \override Score.JumpScript.Y-offset = 0
          \startStaff % resume bar count
          \cadenzaOff % show staff lines again
        }
      }
    }
    \sectionLabel "Coda"
    % Show Coda on a new line
    \break
    \repeat unfold 8 { c4 c c c }
    \fine
  }
}

\paper { tagline = ##f }