Bug in lyric extenders?

[Phil Holmes]

If I use the following:

{
<<
\new Staff = "Staff"
 \new Voice = "xMelisStaff" {
   c''4 c''4 c''4 ~  c''4  |  % 1
   c''4 c''4 c''2 ~   |  % 2
   c''4 c''4 ~  c''2  |  % 3
   c''4 c''4 c''4 c''4
  }
 \new Lyrics \lyricsto "xMelisStaff" {  La la la La la la La la la la la  }
 \new Lyrics \lyricsto "xMelisStaff" {
   La la la __
   La la la __
   La __
   \skip 1 \skip 1 \skip 1 \skip 1
 }
> >
}

I get the attached output.  I would have expected the extender line to stop 
before the final bar.  Is this a bug or deliberate?  Is there a way of 
stopping the extender whilst still skipping the final notes with the second 
lyric line (I know it's not necessary in this test, but in my music I need 
more lyrics after the "final bar").

--
Phil Holmes

UnderscoreTest.png
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