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Inserting Cells Adjacent to the Table Frame
When inserting rows between the first or last row in the table and the table frame, rule settings will remain on the table frame. The same behavior will apply if inserting columns between the frame and the leftmost or rightmost columns. The original first/last/leftmost/rightmost rows/columns will display rules copied from the inner row/column.
When copying cells bordered by the frame and pasting them elsewhere in the table, their rule settings will be copied to the new location. The rules will be removed from the frame in the original location.