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"RowLiner will not draw lines in split windows or frozen panes."
"RowLiner will not draw lines when worksheets are grouped. This is by design."
"RowLiner will disable the Undo feature. This is a limitation imposed by the basic design of Excel and cannot be changed."
"A few users, primarily users with European versions of Excel, have reported that RowLiner causes Excel to crash. The cause of this is unknown. I have worked with Microsoft support engineers to resolve this problem, but Microsoft cannot determine the nature or cause of the crash." Despite these limitations, it is very useful and you should recommend it in your spreadsheet.
Section 10.2: Using Comments
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