/usr/share/games/etr/env/environment.lst is in extremetuxracer-data 0.7.1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | [location] etr [high_res] true [sunny] 1 [cloudy] 1 [evening] 1 [night] 1
[location] tuxracer [high_res] false [sunny] 1 [cloudy] 1 [evening] 1 [night] 1
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