This performer slot is not used in the section.
The section legend should describe the performer styles that actually occur in its lyrics. Remove the unused slot to keep the header and formatting in sync.
Example
[Verse: A & <i>B</i>]
Only A sings[Verse: A & <i>B</i>]
A sings
<i>B sings</i>The fix
In the workbench this finding carries one control, labelled Remove unused performer slot. The fix is classified as safe, so pressing it applies the edit directly — one press, one undo step.
Source
The guideline this rule enforces, as cited on every finding it reports:
Use song part headers verified Section headers, performer legends, and four differentiation styles