Practically, looking for an appropriate override to move the \mark a bit off the system.
There is enough space around and I would like to use it, so that the content is not too cramped together.
I suppose you want something like this?
\new DrumStaff {
s1*4
\section
\once\override Score.RehearsalMark.self-alignment-X = #LEFT
\once\override Score.RehearsalMark.padding = #3
\mark \markup\box "Bridge"
s1*4
}
self-alignment-X
changes horizontal alignment. I would think Y-offset
should be used.