I don't use any Google services outside of small tests like this, but it still makes me concerned for how this will affect the privacy of people I know.
On the flip side, those same solutions can no longer set a persistent cookie with the image, so persistent tracking based on the initial email open will stop working.
Has it? If Google's proxy is caching images, then "email open" tracking might have broken entirely. All the sender would see is that their email has been opened once by the proxy -- for all gmail addresses put together.
Or, if they snip the GET variable for whatever reason (I don't see them doing this):
http://example.com/gmail/{yourusername}/trackingimage.php
Or even:
http://example.com/{emailidfromadatabase}/trackingimage.php
This tactic is already in use by most mass email companies.
A solution would be 1-pixel high tracking lines - a 1 x 128 pixel wide image that encoded 0 and 1 as two RGB colors adjacent to the mail's background color in the visual spectrum so the difference isn't noticeable would encode a sha-1 hash placed in the url.
http://example.com/tracking-line/{hash}.pngThat would essentially render open statistics meaningless and would let Google cripple another industry after the promotions tab and 'not provided.'
I really hope they don't because it's such valuable information when creating email copy...
first one = Google
second one = user
No, it didn't. If you had chosen the option to ask before displaying external content -- which existed and applied to non-image content and, without which selection, email-open tracking by external non-image content was already reliable -- then the new setting to ask before displaying external images is selected for you by default.
If you hadn't selected that option before, you weren't protected from "email open" tracking.
If you didn't have the "ask before displaying external content" option set before this change, you were "opted-in" to read receipts already -- its just that, due to protections designed to stop other malicious use of images, you were incidentally protected against images as the vector for silent read receipts.
With this change, you are better protected against the malicious uses of images the default-not-to-display option was designed to protect against, but exposed to external images as a vector for read receipts if you hadn't chosen to display external content only after confirmation. If you did choose that previously, then you also got the new "ask before displaying external images" chosen by default -- so if you were protected from senders injecting read receipts before, you still are now. If you weren't before, you aren't now, but then that's not really a change.
> Instead of serving images directly from their original external host servers, Gmail will now serve all images through Google’s own secure proxy servers.
In most cases, the unique identifiers are embedded in the URLs themselves, so simply serving through a proxy is ineffective. Should I blindly trust that you, Google, did the right thing?
Edit: looks like Google isn't stripping out the query parameters AND it isn't proxying for iOS devices! This is by far the least effective set of decisions... http://blog.movableink.com/gmails-recent-image-handling-chan...
I wonder if this change is a result of backlash over the promotions tab. These type of referenced images are most commonly used in marketing campaigns and were from businesses likely to pay good money to AdWords. As a concession for fewer overall impressions, perhaps, these groups got Google to let them track easier? The whole thing smells fishy.
How this plays out will be interesting to watch.
Are you saying squash the sender or squash the tracking images?
I hope gmail doesn't start squashing my emails because it contains a tracking pixel.
FTA: This new improvement will be rolling out on desktop starting today and to your Gmail mobile apps in early 2014.
See how marketers are scrambling to adjust to this change:
a.) Gmail is now requesting all images from proxy servers (googleusercontent.com), which incorrectly situates users in its headquarters in Mountain View, California when images are downloaded. This impacts the ability to geo-target image content for those Gmail users who are affected by the changes. (Note: Local Maps using zip codes appended as query parameters are unaffected.)
b.) Gmail is stripping the user-agent headers from the client request, which eliminates the ability to determine the Gmail user’s device and target image content appropriately.
c.) Gmail is removing the cache-control headers from the responses, which forces the user’s images to be stored in their browser’s cache for up to a day. This only impacts live image content if a Gmail user re-opens the email after the first open.
...
http://blog.movableink.com/gmails-recent-image-handling-chan...
Basically their only avenue for now is mobile email which will soon follow in adopting this method.
And, as such, OP's claims are exactly correct.
The only way this would not be true is if GMail pulled every image in every email, even if it's not read by the recipient. Given GMail's usage of the term "proxy server" in their blog post, as well as the tests by the OP and others on this thread, this appears not to be the case.
http://marketer.com/4b3403665fea6.jpg
where that hash is used to link to my email address
It will protect you from it being as a read receipt if (and I'm not sure if this is the case, though it should be trivial to test by sending email with images served from a site you control to an email you control without opening it) Google requests the image once it has received the email.
I'm sure they built-in rate-limiting to prevent DDOSing the sender's image server...
It protects you from the guys at marketer tracking your user-agent, your ip address (which gives a rough geo-ip), the number of times you opened the email, etc. It's unclear to me whether the images could set cookies before (they probably did), but even without that, they could just use etag-tricks, or stuff like that, to track you cross-sites.
Marketers might now know when you open the message, but proxying the image prevents them from getting more precise information.
(No idea exactly how much of this and more Google does, obviously, but they put themselves in position to do it)
[Update: I'm not sure when this feature will actually be rolled out. I think my test below automatically displayed the image because my own email address appears to be implicitly a whitelisted sender (even though "images from this sender are always displayed" doesn't appear for it). Whether Google will alter the behavior when they actually deploy this feature, I don't know.]
[Original message:]
I just tested and, yes, Gmail only loaded the referenced image when I clicked on the message to open it within Gmail. I can't be sure, because perhaps if I had waited an hour without opening the message, Gmail would have automatically loaded the image anyway. But in reply to mherdeg below, the evidence suggests that, yes, Gmail plans to opt everybody in to sending "read receipts" by default for HTML messages that reference images.
I'm surprised by Google's statement that the previous behavior of prompting was "to protect you from unknown senders who might try to use images to compromise the security of your computer or mobile device."
I realize this was a benefit, but I always thought the main purpose was for privacy --- not to betray to the email sender when I opened the email. My guess is that Google did not view this as a privacy setting, or they probably would not have forcibly changed everybody's setting.
It's doubly strange that they did so without a notice inside Gmail that they did so -- just a blog post.