Turn lead sheet into a blank staff

[Sandro Santilli]

I'm producing lead sheets with lyrics, melody and chords
and would like to extract from them som blank sheets with
just lyrics and chords so that players can take their notes
onto (for solos or arrangements).

My first attempt has been with using \hideNotes but that one
still keeps some elements (courtesy accidentals, ties, slurs,
tuplet indications, fermata sign).

I'm trying with a custom \hide command, defined as follows:

  hide = {
    \override NoteHead #'transparent = ##t
    \override Stem #'transparent = ##t
    \override TupletBracket #'bracket-visibility = ##f
    \override TupletNumber #'stencil = ##f
    \override Accidental #'transparent = ##t
    \override Tie #'transparent = ##t
    \override Slur #'transparent = ##t
    \override Dots #'transparent = ##t
    \override Staff.LedgerLineSpanner #'transparent = ##t
    \override Beam #'transparent = ##t
    \override Rest #'transparent = ##t
  }

but with it I'm still having fermata and courtesy accidentals.
Idea how to override them to be also transparent ?

--strk;