Hi Jean,
If you don't want to fix your files manually, you could add a redefinition of \afterGrace that doesn't have this optional argument, like this:\version "2.22.2" afterGrace = \afterGrace \afterGraceFraction \etc \language "english" \relative c' { d2 \afterGrace 4 { cs16 d } }
Sorry for duplicating your reply (although it's kind of funny we gave exactly the same half-ideal remedy).
The reason is that for some weeks now, I've been having issues with mail delays on the LilyPond mailing lists: I routinely receive e-mails 1-2 days late, and most of the time, I see replies to messages that haven't arrived yet. While I'm sure no information gets lost in the long run, this nevertheless has taken the fun out of following the lists a bit for me.
I changed my subscription now to using a different e-mail address, maybe this will improve things: It just might, as I received the "welcome" message immediately on the address I've switched to, while the unsubscribe confirmation hasn't arrived yet on the old address.
Lukas
