Leger lines
Leger lines are small extra horizontal lines that help show the position of notes that are written outside the five staff lines.
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If you encounter an excess of leger lines it might be wise to introduce a clef change or ottava (8va/8ma).
Width (length) and weight (boldness) of leger lines can be adjusted in the [Options|Layout] dialog.
During edit, you wil see dotted leger lines when hovering the mouse on locations where leger lines are needed:
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