Gracenote bug?

[Kees van den Doel]

Trying to shift a note away from the barline which it's touching by adding a \grace s16, but I ran into what appears a bug?

\version "2.22.1"

mus = \relative {
  \repeat volta 2 {
    c'1
  }
  \alternative {
    { c1}
    { \grace c16 c1}
  }
}
musb = \relative {
  \repeat volta 2 {
    c'1
  }
  \alternative {
    { c1}
    {c1}
  }
}
\score {
  \new PianoStaff <<
    \new Staff <<
      \musb
    >>
    \new Staff <<
      \mus
    >>
  >>
}

test1.pdf
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