What's something you consider to be a red flag that most others probably don't?

I actually see red flags before I talk to someone.I consider it a red flag when some one treats others badly. This can be rudeness, coldness, or lack of empathy. I know right away I want nothing to do with someone like this. I walk away from people like that,or block them on SW,when I see them being mean to others.

Starting off in the "getting to know you" stage with complaining about their ex.

If he walks into a room before me
it's a no

Insensitivity to shy and quiet people.

Red flag laws. Its the next step in the eventual complete loss of due process.

Complaining about past experiences on your dating profile.