Re: runover staff lines with hidden time signature

Alan Shaw wrote:

I've seen discussion of a similar situation at the end of a line, where it can be fixed by adjusting break-visibility, but this is a little different. What I am trying to do is set certain passages where a choir and instruments play together, and the instruments then repeat without the choir. In the simplified snippet here, the first line shows basically what I want. The second line differs only in that the time signature changes right at the volta, and though I am able to hide the new time signature in the choir part, the staff lines around it still get drawn before \stopStaff takes effect. How can I fix this?

\version "2.12.2"

\layout  {
\context  { \Score
\remove "Volta_engraver"  
         } }
       
\score {
\relative
<<
%% no left repeat sign and chorus staff stops cleanly before volta bracket
\new Staff <<
{  \time 4/4 c'4 d e f \once \set Staff.whichBar = "|"
\repeat volta 2 {  a, b c d \stopStaff }
            \alternative  {
                 { s1 | }
                 { s1 | }
             }    
\break
\startStaff
 c4 d e f \once \set Staff.whichBar = "|"
\repeat volta 2 { a, b c d \stopStaff  \once \override Staff.TimeSignature #'stencil = ##f  \time 3/4 }
            \alternative  {
                   { s2. |   } % new time signature suppressed, but staff lines still run over
                   { s2. |  }
             }        
\startStaff          
        }
      >>      
\new Staff \with {
        \consists "Volta_engraver" }
<<
{ \time 4/4 c,4 d e f
\repeat volta 2 { a, b c d }
        \alternative  {
             { c2 d }       % instruments repeat
             { r2 r4 e8 e }
          }
\break
c4 d e f                
\repeat volta 2 { a b c d \time 3/4 }
            \alternative  {
                   { r4 r8 e8 e4 }
                   { fis8 g8 fis8 g8 fis8 g8 }
                 }
             }  
        >>
>>

\layout {   }
}