S3 CORS, always send Vary: Origin

Question

I am using an S3 bucket behind Cloudfront with CORS enabled. If the client makes a request with the Origin header, then S3 (and cloudfront) respond with a \"Vary: Origin\" h

Answer 1

I made an account just to answer your question, because there are very few good answers around for this kind of problem (and a few related ones).

The problem you describe happens for some reason primarily in chrome, FF and IE seems to be smart enough not to share cache between AJAX and regular calls in these instances.

The Problem

Lets first describe why the problem happens for future readers:

• Browser (Chrome) ask the server using a regular or