Bright 2x2 pixel spot on laptop display

I have a Samsung NP550P5C laptop with a problem on the display I've never seen before: it has a 2x2 pixel area that is considerably brighter than the rest of the screen area. Here's a closeup:

The pixels work otherwise fine and are not stuck at white. If I adjust screen brightness, the spot gets brighter too. If the spot is on a dark area it's completely unnoticeable. It's a LED backlit panel - are the LEDs really that small?

What could cause this problem and is there some way to fix it? The laptop is still in warranty but I know they will just give me a new one in exchange and that means more hassle with the software installations and all than I'm ready to go through for such a small, albeit annoying problem.

Edit: I did the suggested test with the Chrome extension, here's what the bright area looks like on other colors.

Here's a few things you can try:

1. Try tapping the screen (gently) where you see the dead pixels.
2. This Chrome extension can help verify whether you're dealing with dead/stuck pixels.
3. Jscreen Fix can sometimes re-energize stuck pixels, as well as remove burn-in from LCD and plasma screens.

This is not a dead pixel, it's damage in the diffusion foil behind the LCD! In most cases, mechanical pressure is the reason, likely, there's no fix, you'd have to replace the screen...