Hacker News article It’s a joke: a Facebook login for a Facebook-powered joke site.
This prank will let you log in to the Facebook Messenger app, where you’ll be greeted with a photo of a smiling person laughing, with a caption about the “joke” being performed.
But the joke site will also redirect you to a Facebook page, in which you’ll see the same picture of a grinning person laughing.
The joke site then takes your login credentials and sends them to the joke website, which will impersonate a Facebook account.
When you click “accept,” you’ll get an error message saying “the login was rejected.”
But when you click the “accept” button again, it’ll redirect you back to the login page, where a page containing the same photo will appear.
It’s all done by a bot called a Facebook Messenger bot.
You can find a screenshot of the bot below, which shows a user logging in to Facebook Messenger from a Facebook desktop browser.