How far the label reaches below the line of its verse: a lyric with line breaks has its first line there, and its further lines below. 0 for a single line. The label is placed by its bottom (below the last line).
The y of the line of the lyric's verse relative to the staff line, where the lyric's first line, its dashes and extend line are.
Puts the label back where it was before the first layout calculation, called before each calculation. MusicSheetCalculator.calculateSingleStaffLineLyricsPosition() moves the label below the staffline, but the bounding box of the staff entry is calculated from its children (including the label) before that, e.g. in VexFlowStaffEntry.calculateXPosition(). Without the reset, a re-render would include the previous render's position of the label there, where the first render included the initial one - e.g. after a resize, a staff entry whose lyrics were lower in the previous layout kept that lower bottom border, making the page taller. The first call takes the snapshot of the initial position.
The graphical counterpart of a [[LyricsEntry]]