Per [JavaScript on whole site is broken in IE (9 or less) because of stub.js](http://meta.stackexchange.com/questions/176467/javascript-on-whole-site-is-broken-in-ie-9-or-less-because-of-stub-js):

> We are trying to block a scraper that is scraping against our terms & conditions.

> This bug was an unforeseen consequence of trying to ban them client side - not realizing that atob is not supported by IE 7/8/9 (and 10 in 7/8/9 mode).

> I am reverting the change and deploying as we speak.

Things should be back to normal soon-ish.