How do you intend to fix this properly? I'd rather avoid adding a hack to the XBlock at this point, since we are in the cleanup phase.

Since the issue is that CORS requests can't be async in Firefox, I see two options: either the discussion app is updated to handle async requests, or the requests should not be crossDomain (ie we reverse proxy the LMS endpoints on the apros nginx to have them on the same domain as apros)