It could identify when they were feeling worthless or helpless or like a failure, and [Meta] would take that information and share it with advertisers

the company was letting advertisers know when the teens were depressed so they could be served an ad at the best time. As an example, she suggested that if a teen girl deleted a selfie, advertisers might see that as a good time to sell her a beauty product as she may not be feeling great about her appearance. They also targeted teens with ads for weight loss when young girls had concerns around body confidence