Clearing Safari website data does not delete everything - iPhone

Zero byte cookies are just place holders...this helps them know that you have already been to a site. It is also used by AdChoice and other roaming ad companies, etc. This is the part that maybe was agree to just stick around. I know that a website can track you with a zero byte file by the file name alone....

This is all kinda of like big brother to me, I was told, that one of the browsers was working in a time limit life of a cookie or database before it would totally deleted. Enough time to do what you need on the site, then zap the cookie.

<<[Lady Engineer]Zero byte cookies are just place holders. This helps them [cookie creators] know that you have already been to a site. It is also used by AdChoice and other roaming ad companies, etc.>>

Lady Engineer, thanks for for providing the link to Ben Lovejoy's techie article detailing what those 0 byte and larger cookies can reveal re our browsing activities — https://9to5mac.com/2017/09/15/what-are-cookies-how-do-cookies-work/

It helps supersede the effort by some to downplay how little privacy protection we have due to the cookie retention policies of Safari and some other browsers.

In the end, it is the unknowing bargain we have to make to use free software.

ParhamS wrote:

iOS 11 option

Always Block

Prevent Cross Tracking (the most advance technology blah blah)

Prevent cross tracking blocks third party cookies. That's what third party cookies do; allow third party tracking. Apple has taken it one step further. See: How Apple is taming the ad biz. Just don't expect Google or Zuck to follow • The Register

https://martechtoday.com/digital-advertising-industry-responds-apple-intelligent -tracking-prevention-204141

https://techcrunch.com/2017/06/05/apple-adds-a-tracker-blocker-to-desktop-safari /

http://trafficjammedia.co/what-is-apples-intelligent-tracking-prevention-and-how -will-it-affect-ad-targeting-and-user-tr…

I don't believe this has anything to do with the type of iPhone - in our house we have two iPhone 6s's, 1 iPhone 6 and 2 iPads. It only happens on one 6s. I suspect that it has something to do with past applications that were installed, that's the main difference between the device. Indeed, two of the 6s's are on the same Apple ID and only one of them has the problem. In my case I have exactly 10 well known website cookies (e.g. Google, Washington Post, and New York Times) that won't go away when I clear. Even if I actually open a web page and sign in, the cookie becomes a non-zero cookie. But if I delete it, it remains as a zero cookie. I wonder if content blockers (e.g. Umbra?) could trigger this - I had installed one such app but removed it quite a while ago...

Apple clearly knows about the issue with the "evercookie". As with all behaviors and functionality they are not about to fix it, possible reason? Well, lets just say its a true privacy issue

Confirmed.

Thanks Apple.

You're not going to like this reply.

Yes, many people are having the exact same problem. After approximately 3-4 hours of trying every solution I could find in these forums and not having any success, I took my MacBook Pro to an Apple Genius Bar. For nearly 1.5 hours, they tried nearly every solution they could think of and running diagnostics on hardware and software, then restarting the computer, etc - all without success. Finally, one of the top guns believed regardless of the diagnostic results, there may be a software glitch some where and suggests wiping the entire computer clean and reinstalling and starting all over.

I took the computer home and reinstalled my backup data. Guess what? That did not solve the problem. Removed website data reappears within seconds.

Not very encouraging. The techs at the Genius Bar also agreed that as the web site data list continues to grow, it could eventually slow the speed of the computer.

I found iOS 10.3.3 did NOT delete all the cookies on my iPhone 7.

At the time of the upgrade there were pages of cookies — most showing 0 bytes. After the upgrade, but before opening Safari or any apps, I clicked Settings>Safari>Clear History and Website Data. When I then went to Settings>Safari>Advanced>Website Data, I found the cookies on the left panel still remained.

I then clicked on Settings>Safari>Advanced>Website Data>Clear All Website Data. When I reopened Website Data the same cookies in the left panel still remained.

I then deleted each cookie manually and closed Website Data. However, when I reopened it, the cookies in the right panel had reappeared. Again I deleted them manually, but when I reopened Website Data, the cookies in the right panel had still reappeared.

Something permits intrusion on the Safari cookie folder. I have never banked with Citibank or any affiliate of which I know. I do have apps for the other cookies. Perhaps some have something to do with Apple Pay

Interesting, but that doesn't explain why you can't delete zero length cookies which obviously contain no data of the type that article describes, and why it has worked this way for over a year, long before ITP was ever mentioned. Which comes back to the fact hat it's a bug.

There is still a problem with this. My son was searching the web (I was with him) and was looking for information on Ricky Nelson, for a report he's doing. Later I showed him how to clear his browsing history, when I noticed two cookies whose names suggests that he visited some illicit sites, which he didn't. The fact that it has zero bytes is not my concern - it's the name of these two cookies. Sometimes teachers randomly check student's phones (when they use them in class - that's another story) and I'm trying to avoid problems. No matter what Apple is doing, the end user should maintain the right to delete whatever he/she wants.

Thank you, but I am not concerned with what the cookie contents. It is the name of the cookie I'm concerned with and want it deleted. The iPhone 7 deletes all other cookies but these two for some reason.

ParhamS wrote:

Are you bored? This is pretty much trolling.

No, I find this thread very interesting. I'm not sure to which post of mine you're referring. However, if it's the one providing a practical suggestion on how a young man can avoid getting in trouble at school until such time this issue is resolved, I don't see how that could be construed as "trolling". What practical suggestions do you have to offer?

Lawrence, I hear what you’re saying and I have read the articles. However my iPhone 7 Safari cookie listing shows third party cookies are still being added for sites I have not visited, even though I completely deleted everything a couple days ago after installing iOS 11

. The pic below shows one of many pages of cookies on my iPhone . Those marked in red are sites I did NOT visit.

How do we explain that?

cyberbiker wrote:

I’ll bet you will have accumulated pages of cookies, only some of which you will recognize from visited sites.

Not yet. I have cookies from sites I've visited, a couple from apps I've used, and doubleclick, which I know all about.