Title text:
People say setting of fireworks indoors is dangerous, but I looked at their energy release and it’s like 10^-40 foe; totally negligible.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3208/


To understand the “title text” section: https://en.wikipedia.org/wiki/Foe_(unit)
Foe is a unit to describe the amount of energy released by supernovae.