Why is console.log an empty function on some sites in Chrome?

Question

Go to Twitter\'s login page and type the following in the console:

window.addEventListener(\'keypress\', function(e){console.log(\'hello\')}, true)

Answer 1

Get it from an iframe:

function setConsole() {
  var iframe = document.createElement('iframe');
  iframe.style.display = 'none';
  document.body.appendChild(iframe);
  console = iframe.contentWindow.console;
  window.console = console;
}

(and then call it)

setConsole()

source: https://gist.github.com/cowlicks/a3bc662b38c36483b35f74b2b54e37c0