There is safety in numbers
We check ourselves in the mirror.
Chatter between the stalls only goes on if the women in the restroom know each other. It is rare that anyone will actually strike up a conversation in the restroom with a stranger.
The Second and third stalls always seem to go first. At least in America, if someone is in the second, the next person to come in will take the fourth ( if that's an option.) I don't know about elsewhere, but I do know here that Americans like their space.
Most of the females I know always check the toilet paper situation before they do their business. But, they will ask if there isn't any available.
We go in packs to chat. And no, we aren't always talking about males. Lots of times we talk about other females.
We check our hair, our makeup, to see if our ass looks big in the pants we have on.
Of course these are just generalizations, different women, and different groups of women definitely have their own practices.