Bug in \offset with Fingering.font-size?

[Trevor Daniels]

Should \offset work with the font-size of fingering?  It doesn't seem to.  The 
default value is -5, so offsetting by -2 should give -7, with a size as shown 
by the \override and \tweak, but both forms of \offset give 0.

{
  \set fingeringOrientations = #'(left)
  <a'-2>4
  \override Fingering.font-size = #-7
  <a'-2>
  \once \offset font-size #-2 Fingering
  <a'-2>
  <a'-\tweak font-size #-7 -2>
  <a'-\offset font-size #-2 -2>
}

Trevor

test.svg
Description: image/svg