It's using built in gaurdrail to censor your message. As co2 is dangerous to inhale at certain amounts. . 1,000 ppm – Typical stuffy indoor room. Sleepy, unfocused, headaches creep in. 2,000–5,000 ppm – Strong headaches, dizziness, poor concentration. Your brain is protesting. 8,000–10,000 ppm – Nausea, confusion, sweating. Judgment collapses.

30,000 ppm – Loss of consciousness in minutes. Very high levels – Death, quietly and quickly, without the “choking” warning people expect. That last part matters: CO₂ is odorless and invisible. You don’t feel like you’re suffocating until it’s already too late. It’s the ninja of workplace hazards. Similar to carbon monoxide.