Temporary Editor-lite permissions in Lab-like environments for designing and experimenting.
Mods introducing new content into the game.
Pollution appears as a visible smog (or spore) cloud, covering your factory. The more you pollute, the less you can see. Optionally reduce solar power effectiveness based on how much pollution is over each panel, to promote placing panels far away from heavily polluted areas.
Small changes concerning balance, gameplay, or graphics.