Breaking LilyPond tuplets across a line

LilyPond refuses explicit midduration \breaks by default. Here voice one houses explicit line-breaking information and voice two houses the real musical input. But even so the tuplet refuses to break across the line.



Here the tuplet does line break.



The second example \removes the Forbid_line_break_engraver from voice two explicitly. The first example does not.

   \new Staff <<
      \new Voice {
         s1 \noBreak
         s1 \break
         s1 \noBreak
         s1 \break
      }
      \new Voice \with {
         \remove Forbid_line_break_engraver
      } {
         c'1
         \times 4/5 { c'2 c'2 c'2 c'2 c'2 }
         c'1
      }
   >>

It does not work to \remove the Forbid_line_break_engraver from the Staff, StaffGroup or Score contexts; only Voice and derived contexts implement the engraver in question.