No Expires header on widget resources (no browser caching)

The following URLs used by the Feedback Widget do not have a far-future Expires header set on Amazon S3:

http://s3.amazonaws.com/getsatisfacti...
http://s3.amazonaws.com/getsatisfacti...
http://s3.amazonaws.com/getsatisfacti...
http://s3.amazonaws.com/getsatisfacti...
http://s3.amazonaws.com/getsatisfacti...

This causes them to be re-fetched by the browser on almost every page view. This unnecessary reloading impacts the performance of the website with the Feedback Widget installed. Since most of these are images and therefore are unlikely to change, there's no need to have the user's browser constantly re-download them. The Javascript file can also be cached: it changes rarely, plus it's versioned with the URL.

By the way, setting an Expires header would mean that if a user visited *any* site with the Feedback Widget, the resources would be cached even for subsequent visits to other sites.

Here's an example header that should work:
Cache-Control: max-age=604800

References:
Tip 4: http://www.labnol.org/internet/amazon...
http://www.drunkenfist.com/304/2007/1...