Green screened when exsploring new chunks.

[still crosshair]

So I have been working on something needing the special ice from the ice biomes. I forgot where the one I found was located since its been a few months and I did not place any lights leading to it. So I started flying in a random direction to find the biome. I passed over some mountains and got a greenscreen. I took a picture of it, have no real clue why I got a greenscreen.