Odd behaviour when score begins with grace notes

[H. S. Teoh]

Hi all,

I'm noticing some odd behaviour with the latest version of Lilypond (git
master, nominally 2.25.21). I have a piano score (GrandStaff with two
Staff's underneath), and when one staff contains grace notes right at
the beginning, it throws off alignment of the key/time signatures and
clefs with the bottom staff, and inserts extraneous key/time signatures.

If the grace notes are removed, everything goes back to normal. (See
commented-out line below.)

Here's the simplified Lilypond input that reproduces this problem:

------
\version "2.25.21"
\score {
        \new GrandStaff <<
                \new Staff {
                        \clef treble
                        \time 4/4
                        \key aes \major

                        \relative c' {
                                | \grace {ges'='16 g} aes='4  aes aes aes |

                                %% Replacing the above line with the one
                                %% below makes the problem go away, but
                                %% sans grace notes:
                                %| aes'='4  aes aes aes |
                        }
                }
                \new Staff {
                        \clef bass
                        \time 4/4
                        \key aes \major

                        \relative c {
                                | c=1 |
                        }
                }
        >>
        \layout {}
}
------

What am I doing wrong?  And what's the right way to typeset grace notes
that begin the music?


--T