In IE11 framing fails at setImmediate() call, probably due to an Internet Explorer-specific bug which requires setImmediate() to be called only on window context.

There is already a check related to this issue for IE10 but it doesn't work on IE11 because it defines setImmediate function:
https://github.com/digitalbazaar/jsonld.js/blob/master/lib/util.js#L37

EDIT: It also fails in Edge for the same reason.