I'm getting the auth promp on Chrome.
You're getting it when you visit the site directly.
Opera and Chrome have a policy that is checked when opening the prompt. They ask, "Is the website we're at now the same as this image which required auth?" If the answer is "no", it shows a broken image. If you visit the site directly, you get the prompt.
FireFox, IE, and Safari DO NOT DO THIS. Meaning, when you open THIS PAGE in FireFox, you get a prompt saying your Facebook details need to be resubmitted
while browsing Blockland.