
Beginner's guide: Press F12, then a part of your firefox (if you don't use firefox, please do) opens a view into the inner workings of the web page. Then you click on "Console" (German: Konsole) in the upper part. There you find a "prompt", a kind of input line, often starting with ">>". You have to copy the text of @selfsame
's toot into this prompt – the complete text from "document..." until "...}deg)`)". Hit enter, and F12 to close the Console, and enjoy!
Get back to normal: ctrl+shift+r
@selfsame
I've read 'Punish!' on the button.
Too hard for me -_-