OP might have meant when Facebook exhibits another attribute closely resembling a skinner box [1]. Or the use of their platform as a world scale behavioral analysis experiment.
"An operant conditioning chamber permits experimenters to study behavior conditioning (training) by teaching a subject animal to perform certain actions (like pressing a lever) in response to specific stimuli, such as a light or sound signal. When the subject correctly performs the behavior, the chamber mechanism delivers food or another reward. In some cases, the mechanism delivers a punishment for incorrect or missing responses."
[1] https://en.wikipedia.org/wiki/Operant_conditioning_chamber
"An operant conditioning chamber permits experimenters to study behavior conditioning (training) by teaching a subject animal to perform certain actions (like pressing a lever) in response to specific stimuli, such as a light or sound signal. When the subject correctly performs the behavior, the chamber mechanism delivers food or another reward. In some cases, the mechanism delivers a punishment for incorrect or missing responses."
https://www.theverge.com/2016/1/4/10708590/facebook-google-a...
"Facebook made its Android app crash to test your loyalty"
http://www.telegraph.co.uk/news/12161461/Facebook-addiction-...
"Facebook addiction ‘activates same part of the brain as cocaine’"
http://www.sciencedirect.com/science/article/pii/S0191886911...
"Narcissism on Facebook: Self-promotional and anti-social behavior"
https://www.forbes.com/sites/kashmirhill/2014/06/28/facebook...
"Facebook Manipulated 689,003 Users' Emotions For Science"
https://twitter.com/niftyc/status/482925976251154432
"#facebook emotional contagion study effect sizes are small--probably nobody was driven to suicide. #jokingnotjoking http://www.pnas.org/content/111/24/8788.full …"