Chrome is working as intended: http://crbug.com/180007 http://crbug.com/180007 Github serves pages from 'raw.github.com' with an "X-Content-Type-Options: nosni

Chrome is working as intended: http://crbug.com/180007 http://crbug.com/180007 Github serves pages from 'raw.github.com' with an "X-Content-Type-Options: nosniff" header, which specifically disallows browsers from trying to second-guess MIME types. FWIW, IE has supported this header for years, and Firefox is probably going to be adding it soon as well. So if you're serving your .js files with the wrong content type, they're going to break for more and more users as time goes on.