To paraphrase adelikat: It should remember the row under the cursor on mousedown and select from there to the cursor, i.e. moving the cursor away from the start enlarges the selection, and moving the cursor back shrinks it.
Current behaviour is that any row the cursor passes over while the mouse button is held (not rows between the last touched and the cursor) are added to the selection.
To paraphrase adelikat: It should remember the row under the cursor on mousedown and select from there to the cursor, i.e. moving the cursor away from the start enlarges the selection, and moving the cursor back shrinks it.
Current behaviour is that any row the cursor passes over while the mouse button is held (not rows between the last touched and the cursor) are added to the selection.