CSP3: Consider adding a 'clone-src' directive #199
Description
SVG has a element which is supposed to reference some other markup and have the document act as if the was replaced by that markup. In Firefox, is implemented by cloning the referenced content into the , whereas in other UAs I believe they redirect rendering off to the original content (with some on-the-fly restyling to inherit style in from the ) without cloning. The 'img-src' and 'frame-src' directives are not appropriate (at least in the case of Firefox) since the linked content will end up inline in the referencing document.