Can you set the Same-Origin Policy to be more strict?
<p>I have a situation where users are able to define CSS for specific areas of the site that they maintain. They are able to insert remote resources into this document, and subsequently log IP requests made to these resources by guest users visiting their pages.</p>

<p>Short of adding a purification system that filters remote URLs, is there a way to instruct the client not to make <em>ANY</em> foreign requests? My site is 100% self-contained at the origin and makes no foreign CDN requests. I basically want it so that any foreign request is blocked.</p>