The Linefeed at the end of each row in the csv format is due to Jasper's limitation.
---> When exporting the Jasper Report to a .csv file, each line has a "Linefeed" at the end. (It is because of the condition status what we show in Red/Green/Yellow color in a text field inside a text field. It is the Jasper design limitation.)
---> Because of the design (where the Condition color is placed in the text field inside a text field), to maintain the gap and distinguish between two rows (two colors) the inner text field is adjusted to fit in the row textbox and maintained a gap to top and bottom alignments.. Jasper creates a new row when it finds this kind of gap and translates this as the Row splitter when we export to Excel / CSV.
This is a known anomaly in Jasper Design.
This has been discussed with CABI team also. If we want to remove that extra line then the UI look and feel will be changed. In the attachment, you can find a screenshot of both current and new changes. With that new design, the new line feeds/extra line in the csv / excel will be removed.
This modification will require a patch. If you need it, please open a case and contact support.