I would like to change the definition of `\f` to something like this
```tex
"f" = #(make-music 'AbsoluteDynamicEvent
'text "f"
'tweaks '(((DynamicLineSpanner . horizon-padding) . 0.1)))
{ \stemDown f'4\f f'4\p }
```
to handle issue #4159.
However, if I do the above the `horizon-padding` property can no
longer be overridden with `\tweak` or `\override`. How can I fix
that? In other words, I would like to set the `horizon-padding`
property for `\f` as if I provided a default value for the
`DynamicLineSpanner` grob in `define-grobs.scm`.
Werner
