This app displays green, red, blue, white and black in changing intervals on the whole screen.
While it's not proven that it has any effect, it may help* if your device has stuck pixels or a ghost image, which apparently sometimes does happen on the Jolla Tablet.
- It tries to keep the display active while displaying the light show. Keep your device plugged in!
- Do not look at it if you're sensitive to flashing lights! It's weird to look at even if you're not.
- Use at your own risk. It should not do any harm to the device as far as I know, though.
*) When I had that problem, it at least seemed to accelerate the display's ghost image recovery after letting it run for a few hours. Your mileage may vary.
- Somehow found the sources again and removed an old qml import to make it run again, because someone on telegram wanted to try it. Good luck with your display, my dude!