Forcing a clef symbol to be displayed

When a clef sign has already been displayed and it has not been changed to a different clef, then repeating the \clef command will be ignored by LilyPond, since it is not a change of clef. It is possible to force the clef to be redisplayed using the command \set Staff.forceClef = ##t.

\version "2.24.0"

\relative c' {
  \clef treble 
  c1
  \clef treble 
  c1   
  \set Staff.forceClef = ##t
  c1   
  \clef treble 
  c1   
}