Slashed Sixth in chordmode

If you need a slashed sixth degree, commonly found in figured bass, but in chordmode, here is a very basic way of formatting the markup to get it done.

\version "2.24.0"

%% http://lsr.di.unimi.it/LSR/Item?id=549

\paper { tagline = ##f }

myChordDefinitions = {
  <es g ais c>-\markup \super {
    \combine
    6
    \raise #0.3 \rotate #-75 \bold /
  }
}

myChordExceptions = #(append
  (sequential-music-to-chord-exceptions myChordDefinitions #t)
  ignatzekExceptions)

myChordInit = {
  \set chordNameExceptions = #myChordExceptions
}

music = \relative c' {
  c2 f
}

chord = \chords {
  \myChordInit
  c2 f:m6+
}

\score {
  <<
    \chord
    \new Staff \music
  >>
}