Firefox 44 removes privacy feature.

[stan]

On Wed, 03 Feb 2016 23:25:33 +1030
Tim <ignored_mailbox at yahoo.com.au> wrote:

> Allegedly, on or about 02 February 2016, Robin Laing sent:
> > There was an issue with poorly written sites opening hundreds of
> > cookie requests.
> 
> Sometimes I think sites do that on purpose, to attack people who
> selectively choose their cookies.
> 
> I used to use the option to ask about all cookies, but caved-in to
> changing the preferences to allowing cookies for just one session
> (expunge on exit), thanks to crap like that (that option will probably
> disappear, too).
> 
> Unfortunately, this means you get tracked, and you get more internet
> crap in your mail, and targeted adverts, from that.  It's quite
> disturbing to find while you're browsing some site that you consider
> to be completely unrelated to something else that you logged into
> early, that you've been identified by the earlier sites (you don't
> get asked to sign in, to the sites you browse, later on, there's a
> "hello Tim" already in that spot).

I doubt that you are experiencing traditional cookie tracking.  There
are two other ways of tracking that are much more effective: flash
cookies and html5 storage.  

The add-on betterprivacy removes flash cookies (LSO cookies) whenever
the browser is closed, or with other settings, including a timer.

The add-on self-destructingcookies removes cookies whenever a site is
closed (the site tab, not the browser).  

You should look at an add-on called privacy badger.  It is sort of AI,
and monitors links.  If they exhibit behavior that a tracking site
would, it blocks them.  I can no longer read the site forbes.com
because it thinks I have adblocker turned on.  I don't, but privacy
badger is blocking the ad trackers that would allow ads, so they don't
show up.

Unfortunately, I'm not aware of an add-on that blocks html5 storage.
Html5 allows websites to store their information on your computer in a
reserved area.  I presume it was justified with some kind of
persistence or convenience argument, but I think it is inviting abuse.
I remember that I went into about:config and turned off html5 storage
somehow, but I don't remember the details; I think I just searched on
html5 and there was an entry with storage that I set to false, but it
might have been setting the storage size to zero.

Never!, I repeat never!, allow the site addthis.com to access your
computer.  It uses browser fingerprinting to track your web usage.
NoScript seems to adequately prevent it, and I think privacybadger has
it blocked out of the box.

If you don't go with PrivacyBadger, Ghostery is also a good way to
block third party tracking sites, though it uses a look up list rather
than real time determination.

HTH