White horizontal lines on 2017 MBP

Hi everyone

Since yesterday my 2017 13" Macbook Pro is showing straight white horizontal lines all over the screen, especially on colored pixels (black, white and grey don't seem affected). The screen didn't receive any impact and nothing got poured on it. The lines are here all the time, as soon as I light up the Mac. I tried the Apple Hardware Diagnostic on startup but it found nothing. I tried a NVRAM reset but nothing changed. I tried to plug the Mac to an external display and it was working fine on it, so it seems to be coming only from the screen.

I was wondering if any of you ever encountered the same problem and managed to solve it without going for a full screen replacement. My warranty expired so that would be quite expensive to replace. Also, has anyone an idea on what could have caused it? Could it be overheating?

Sorry for the blurry picture, my iPhone needs a camera replacement...

Thanks