Chosen Solution
What is the black thing below the screen connector . I accidentally scratched a little bit part of it which showed the underlying thing is this thing dangerous Update (08/31/2019)
the black layer I circled has been scraped off a bit in the center
The only black “thing” you can scratch under a connector is a silicon foam that’s in place to help protect the small components under it in case of liquid ingress. There’s no danger in removing that, no need to worry, but be careful next time as when you scratch that, it means you’ve applied pressure in the wrong place to remove the connector and you ran the risk of damaging the small components you can now see.