I downloaded the Linux build for this game, and there wasn't any scenery at all. I assume that's a bug specific to that build, since you have scenery in your screenshots (thanks for providing a Linux build though!).
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This is odd, since I compiled natively on Linux and double checked on a different Linux machine. If you would like to try again I made a browser version https://voidsay.itch.io/sneaky (password "betterLateThenNever") so you can see it how its supposed to be.