> I'm not sure if these protections extend to those using third party email clients with these services
In Fastmail's case, those protections don't extend. I've tested this and Fastmail rewrites the image URLs when viewing through their webmail client but passes the message unmodified when fetching via IMAP.
I understand why they'd do this but I'd love to have a setting that says to do this privacy rewrite when using an external client.
Thanks for clarifying. Might be worth shooting them a message to ask for this feature. They've always been good about fixing bugs and at least responding to requests, even if they decide not to pursue it.
In Fastmail's case, those protections don't extend. I've tested this and Fastmail rewrites the image URLs when viewing through their webmail client but passes the message unmodified when fetching via IMAP.
I understand why they'd do this but I'd love to have a setting that says to do this privacy rewrite when using an external client.