Re: possible bug?

[Lukas-Fabian Moser]

And one addition:

> I did try the options you then gave me. (context \score \override 
> SpacingSpanner.strict-note-spacing = ##t and also \override 
> Score.SpacingSpanner.strict-grace-spacing = ##t)

The relationship between those two settings is not at all obvious from 
the documentation:

https://lilypond.org/doc/v2.22/Documentation/internals/spacing_002dspanner_002dinterface
https://lilypond.org/doc/v2.22/Documentation/notation/changing-horizontal-spacing.html#strict-note-spacing
https://lilypond.org/doc/v2.22/Documentation/notation/special-rhythmic-concerns#grace-notes

But in fact, if I read the source correctly,

strict-grace-spacing = ##t

is strictly weaker[1] than

strict-note-spacing = ##t.

So, in your use case: You can forget about strict-note-spacing, since 
the behaviour that interests you is controlled by strict-grace-spacing, 
and strict-note-spacing does the same thing *and more*.

Lukas

[1] For future reference: The two booleans are translated in 
lily/spacing-options.cc into

float_nonmusical_columns_ for strict-note-spacing
float_grace_columns_ for strict-grace-spacing

which both are used

1) in lily/spacing-determine-loose-columns.cc: treat grace columns as 
loose if _either_ of the two properties is true,
2) in lily/spacing-spanner.cc: handle actual non-musical columns; here, 
only float_nonmusical_columns_ is used.