Ask HN: What was all the white smoke surrounding the starship before launch?

This time around they used water, a lot of water which is typical of other launches by the rest of the world to attenuate rocket engine noise. It also does wonders for the launch pad.

So the extra stuff is water particles and steam ...

Following your point, here's a video of their test of the water deluge system: https://www.youtube.com/watch?v=GOtw3ucIKng

Water condensing out of the air because of the cryo fuel.

All engineers know when you let the special white smoke out, that the unit will fail. /s