u/Aromatic_Win5617

When I went to run a playback of my simulation, it added a random mountain image to the background. I cant see a setting to change it. Any help would be great.

https://preview.redd.it/g3rha0q6sdwg1.png?width=2077&format=png&auto=webp&s=3ddc8c068a7d64882436b1cf9fc8530a0e18a790