Yeah, I'm mildly confused by what the sell point here is. I sort of assume that any loading of remote resources automatically represents tracking information for this use-case, every email can be trivially individualized to the receiver and in turn I don't see how it's feasible to prevent resource tracking. You either load remote resources, or you don't. I guess if techniques remain relatively unsophisticated for email and few people bother then individuals might slip under the radar, though partial blocking itself represents a signal. But unlike the web individual messaging remote resources seems like an arms race users would be destined to lose.
The only thing I could see really working would depending on a really big service that processed every received email immediately and proxied all remote resources without any user interaction. Plenty of challenges there too though, and harder to make it work with regular clients. Maybe dynamically rewriting the email to point to the proxied resources? Or automatically rendering/inlining them?
>Maybe dynamically rewriting the email to point to the proxied resources?
AFAIK gmail already does that. It prevents people from knowing your IP address, but they still know whether you opened the email or not, since it's lazy loaded. Preferably there's a email service that always loads the images and stores it, so you can view images without any spying.
The only thing I could see really working would depending on a really big service that processed every received email immediately and proxied all remote resources without any user interaction. Plenty of challenges there too though, and harder to make it work with regular clients. Maybe dynamically rewriting the email to point to the proxied resources? Or automatically rendering/inlining them?