It's insivible but it's present, so NWC makes room for it.
!NoteWorthyComposerClip(2.75,Single)
|Chord|Dur:Half,Dotted|Pos:-3,b-1,n0,3|Opts:Stem=Up
!NoteWorthyComposerClip-End
!NoteWorthyComposerClip(2.75,Single)
|Chord|Dur:Half,Dotted|Pos:-4z,-3,b-1,n0,3|Opts:Stem=Up
!NoteWorthyComposerClip-End
By the way: what about a way, in edit mode, to "see" that something invisible is there?
If I didn't know what's going on I would have been very puzzled and I had to check attentively the nwctxt.