MartyTheGamer's post in ETS2MP Winter mod? was marked as the answer
While it does show in the menu, it is disabled and cannot be turned on. The developers might re-introduce it when winter comes and if there is a compatible winter mod with the then current game version.
MartyTheGamer's post in Game crashes as soon as it loads. was marked as the answer
Switching to temporary 1.18.1 beta on steam seems to have fixed the problem.