A better UX should be "I'm sending this image instead of this one, because of fingerprinting. Are you OK with that? Yes, No send the original image this time."
This would prevent problems but I don't think it can cope with the number of requests in the normal flow of web browsing.
> A better UX should be "I'm sending this image instead of this one, because of fingerprinting. Are you OK with that? Yes, No send the original image this time."
I'm presuming you want the browser to somehow detect whether the garbage image data ends up in a POST request? I don't see how you can implement that in a reliable way, considering there are dozens of ways to go from canvas data to a POST request.
This would prevent problems but I don't think it can cope with the number of requests in the normal flow of web browsing.