FWIW, MuseScore seems to get this right. Perhaps its corresponding part of the code (wherever it might hide) could serve as inspiration for a fix for Lilypond? —Please excuse my ignorance if this is technically nonsense! :-).
On 12. Oct 2020, 09:04 +0200, Andrew Bernard <andrew.bernard@gmail.com>, wrote:
I would be a happy man if the notorious Issue 34 could be resolved. I
spend a lot of time having to put grace note spacers in complex scores
to get the vertical alignment working. Each one I do, I wish I knew
enough about lilypond internals to contribute a fix. It's not clear to
me why this one is so immensely difficult to solve, but I trust the
developers that it's a real doozy.
Andrew
On Mon, 12 Oct 2020 at 17:48, Martín Rincón Botero
<martinrinconbotero@gmail.com> wrote:
Thanks for the link Jean. 8 years old issue? Ouch!