Cross-staff stems cause collisions

[Jean Abou Samra]

   Hi,

   Please have a look at the following example.

   \version "2.21.0"
   % The accent and the dynamic collide in an ugly way.
   \new PianoStaff \with { \consists #Span_stem_engraver }
   <<
     \new Staff { \stemUp e''8 }
     \new Staff { \stemUp \crossStaff { e''8->\f } }
   >>
   % This does not happen usually:
   { e''8_>\f }
   % Actually we can reduce the example even more, althought it
   % does no longer mean anything from the musical point of view.
   \new Staff { \stemUp \crossStaff { e''8->\f } }
   It seems that span stems confuse the algorithm that avoids vertical
   collisions. Possibly linked with
   [1]http://lilypond.1069038.n5.nabble.com/Cross-staff-slur-spoils-collis
   ion-handling-td198796.html
   Regards,
   Jean Abou Samra

References

   1. 
http://lilypond.1069038.n5.nabble.com/Cross-staff-slur-spoils-collision-handling-td198796.html