Reading a message fetches its remote images through this server, so the
sender learns nothing about the reader. Quoting the same message into a
reply fetched them directly: same pixel, same reader, but the request
carried their IP and user agent -- exactly what the proxy withholds.
A quote now proxies them the way the message view does. That alone would
be wrong, because a proxied URL belongs to this deployment: sent
unchanged it would reach the recipient as images only this server can
serve, broken for them and a beacon back here. So buildEmailObject turns
them back into the addresses they came from, beside the pass that
restores images blocked under pr411 and the one that turns editor blob
URLs into cid: references.
Deployments with the proxy off are unaffected: the quote fetches
directly, as reading does there.
Three tests from pr411 asserted the address sat in src when images were
allowed, which was the old behaviour; they now ask whether the draft
fetches it at all, proxied or not.
No new strings.
Replying sanitized the quoted body with allowRemote: true, so quoting
fetched every remote image in the message whatever the reader had
decided about it. A tracking pixel in the quote then reported the
message read, and the address live, to whoever was counting -- the thing
leaving the images blocked was meant to prevent. Edit as new and opening
a draft that quotes a message did the same.
The decision now lives in one place, remoteImagesAllowed(), asked with
the same inputs the reader's answer used: the image policy, the trusted
senders, whether the sender is a contact, and whether Show images was
pressed on that message. The last of those was component state, so it
moves to the mail store, where the composer can see it.
Blocked images already keep their address in data-ihm-remote, so nothing
is lost by not fetching: it goes back on the way out, and the sent quote
is what its sender wrote. The recipient's client decides for itself, as
it would with any other client's reply.
Before pr408 this needed a rich-text default to reach; the format offer
made it reachable from plain text, which is how it was found.
No new strings.
jcoffey