Marice has released a Pixel fixer for the Nintendo Switch:
This program displays different colors to detect dead/stuck pixels on your Nintendo-Switch screen.
It can cycle colors on your Switch screen very rapidly to try and repair stuck/dead pixels.
ScreenTester-NX v0.2
Just unpack the zip to the root of your SD-Card (make sure to keep folder structure intact)
Added Menuscreen
Added rapid color cycle mode (to repair stuck/dead pixels)
Few minor changes
ScreenTester-NX v0.1
Press A for White
Press B for Red
Press X for Green
Press Y for Blue
Press + to return to hb-menu.
Press HOME to return to Switch-OS