I don't know if that's per-design or an oversight, but this makes wiki pages with a number of PNG images slow to reload since the browser can't cache them.
Request URL:https://d3cn662t4iw3q4.cloudfront.net/file/data/<REDACTED>.png Request Method:GET Status Code:200 OK Remote Address:<REDACTED> Response Headers view source Accept-Ranges:bytes Cache-Control:private, no-cache, no-store, must-revalidate Connection:keep-alive Content-Length:30352 Content-Type:image/png Date:Tue, 02 Feb 2016 00:56:12 GMT Expires:Sat, 01 Jan 2000 00:00:00 GMT Pragma:no-cache Server:Apache Strict-Transport-Security:max-age=0; includeSubdomains; preload Via:1.1 cff9911a0035fa608bcaa4e9709161b3.cloudfront.net (CloudFront) X-Amz-Cf-Id:wi1HPbXn7TlOzNzVQyVTNeXg3Ndt9y3oQlAbHHggmEP659_U3xQjEg== X-Cache:Miss from cloudfront X-Content-Type-Options:nosniff X-Frame-Options:Deny Request Headers view source Accept:image/webp,image/*,*/*;q=0.8 Accept-Encoding:gzip, deflate, sdch Accept-Language:en-US,en;q=0.8,fr;q=0.6 Cache-Control:max-age=0 Connection:keep-alive DNT:1 Host:d3cn662t4iw3q4.cloudfront.net User-Agent:Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/47.0.2526.111 Safari/537.36
I also see X-Cache:Miss from cloudfront whenever reloading the images.