For people who don't understand what's going on, you might use a browser extension that blocks external JavaScript. In my case, Ghostery was blocking the Optimi

For people who don't understand what's going on, you might use a browser extension that blocks external JavaScript. In my case, Ghostery was blocking the Optimizely script so I was seeing the normal page. Mailgun changed their Optimizely config to switch all images to kittens and text to kitten-related copy. Well played.