The top left corner of my LCD monitor is acting up. The pixels are colored red and green. Not completely on like a stuck pixel, but variably faded. It's a seemingly random distribution, centered on the corner and fading out after a centimeter. It's very light and unnoticeable - I just assumed it was a pixel defect.
What's confusing me is that the pattern changes depending on the image on the screen. While looking at SuperUser, I see absolutely nothing. On this page, I see a ~3cm triangle. On scifi, it's ordered into 2 segmented columns composed of squares - green on the left and red on the right.
I should note that the top left corner's actual image (not counting the fading) is the same for all of these - just the tabs+address bar of my browser. The pattern sometimes stays with the window - dragging it to the right moves the red&green pixels, although it quickly fades out relative to the distance. I say "sometimes" because certain patterns (scifi) will move, while others (keygenmusic) are stationary.
I'm running Linux, although I recall seeing similar things on Windows. I can confirm it's not the graphics card, as it didn't show up on screenshot.
What's causing this?