It does not seem to be possible to change the size of a Dynamic staff.
Admittedly, at first sight there's no need to, but it means that the font size
of text and the Y-size of graphics like hairpins does not change. This is a bit
of a nuisance - any chance of getting \magnifyStaff to apply to Dynamics? The
following shows the problem:
\version "2.22.1"
\language "english"
\score {
<<
\new Staff \with {
\magnifyStaff #5/7
}
{ \relative {
a'4\f 4 4\> 4
4 4 4 4\!
}
}
\new Dynamics
{
s4\f 4 4\> 4
4 4 4 4\!
}
>>
}
All the best,