How does Facebook put this formatted text in a JavaScript console?

Question

By opening the JavaScript console on Facebook, you are warning that you are not posting anything there to be safe from a scam. This seems like a very good counter measure against "getting your victim to do the work for you." How do they do it?

Answer 1

console.log () can be formatted using inline CSS

It:

console.log("%cThis will be formatted with large, blue text", "color: blue; font-size: x-large");

It will look like this:

Source