Browser: chrome
Example (may be fixed soon though Fixed by using https directly): http://yeoman.io/community-generators.html

Page tries to load http://yeoman-generator-list.herokuapp.com/ which results in: XMLHttpRequest cannot load http://yeoman-generator-list.herokuapp.com/. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://yeoman.io' is therefore not allowed access..

If the page requests the https version directly then it works.