Unexpected behavior of table view with pinned row

Hi Datagrok community,
I have a question about behavior of table.
When I pinned row number 5, I can scroll compounds without jumping to pinned row whith mouse wheel.
But in case of using up key to scroll up the row, when the cursor reached to top of the table, cursor jumped to pinned row.

pinned_row
In this case cursor jumped from row 7 to 5 when I used up key to move the cursor.
Is it expected behavior of the pinned row?
Any comments will be greatly appreciated.
Best,

Taka