Invisible notes bug in Lilypond 2.24.1 when \hideNotes \unHideNotes used earlier

[Rudolf Cardinal]

Dear Lilypond team,

Using GNU LilyPond 2.24.1 (running Guile 2.2), the following example seems to 
generate a note visibility bug:

\version "2.24.1"
\language "english"
\book {
  \score {
    \new Staff = "LH" \with { printPartCombineTexts = ##f } {
        \time 4/4
        \key ef \major
        \clef "bass"
        \partCombine
        \relative c {
          \voiceThree
          % bar 1:
          f-2 ef8-3 f-2 g-1 af-2 \hideNotes bf4 \unHideNotes |
            % if "\hideNotes" and "\unHideNotes" are removed, the bug goes away 
in bar 3
          % bar 2: if you remove this bar entirely, the bug goes away
          c,-5 e-3 f-1 af-2 |
          % bar 3:
          af2.-2 g4-1 |  % Bug: missing/invisible notes! Fingering visible but 
note heads/stems not.
        }
        \relative c {
          \voiceFour
          % bar 1:
          d4_4 c8_5 d_4 ef4-3 ef8-3 d-4 |
          % bar 2:
          c4 e f af |
          % bar 3:
          bf,1-5 |
        }
    }
  }
}

The bug is shown graphically below. In the final bar, the tenor part has 
invisible note heads/stems (although its fingering is shown). If the note 
hiding in bar 1 is removed, the bug goes away – but equally if bar 2 is removed 
in its entirety, the bug goes away. It looks like there is some sort of 
hangover effect from \hideNotes and \unHideNotes that (seemingly randomly) 
affect a subsequent bar. In my original example, the bug occurred 6 bars after 
the hide/unhide bar (rather than 2 bars after as in this example).

all the best,
Rudolf.


[cid:f7b534f7-7b09-499c-bc86-40c6ff4fd7a4]