In Thermal Upgrade, Pufts, while animated inhaling polluted Oxygen, never "bloat up" and don't produce Slime at all, even in highly pollution saturated areas. They also don't spawn vacuum around them, leading me to believe that they don't inhale the pollution at all. Their status is emitting NaN Slime, which effectively is zero. http://prntscr.com/eozd7y
Steps to Reproduce
Find a Puft in Thermal Upgrade. Look at it.
Status: Known Issue
We are aware of this issue and have it logged internally but either we do not have a fix ready yet or we are not planning on addressing the issue in the immediate future.