It looks to me as if the edge of the LCD panel was compromised,
allowing an air leak into the panel.
This might be due to a manufacturing defect, but the radiating pattern
of lines, and the thin little hairline I see at the tip of the
leftmost radiating spike of blue-ness, suggests that the panel was
actually fractured or chipped at its edge... either by impact or by
excessive non-impact pressure. The whitish spots/rings near the top
of the display area suggest that something has pushed or scraped the
protective cover enough to damage the plastic film.
If the recorder was sitting on the floor, is there a possibility that
the place wasn't "out of the way" enough, and somebody accidentally
stepped on it? That might easily flex the plastic cover and put
pressure onto the LCD and crack it. Direct downward pressure by a
shoe might not have left scratches, other than perhaps those small
scrapes/defects just below the top.