"The black uniformity of the monitor is terrible. Backlight bleed is evident almost everywhere on the screen in our overexposed test image. Unfortunately, this is also noticeable in normal content, especially when displaying a uniform dark color background. Note that black uniformity is panel specific and will differ from unit to unit, but we have seen reports displaying similar uniformity."
Review from Rtings
https://www.rtings.com/monitor/reviews/dell/s2719dgf