Nothing shows up when I paste in the console / I get a warning when I try to paste in the console

Some browsers prevent you from pasting code in the console because it could be malicious. This is called Paste Protection and you can read more about it on the Chrome for Developers Blog.

If this happens, follow the instructions in the console to re-enable pasting, and then try again. For Chrome, the following steps should work:

1. Try to paste something in the console. You should get a warning message about pasting
2. Type "allow pasting" in the console and press enter

See this video for a visual walkthrough.