Are you sure that this is about cookies and not about some other data that has these websites?

Does CCleaner tell you where it finds these cookies?

I remember seen mentioned the SiteSecurityServiceState.txt file that stores HSTS data among other data.

• https://developer.mozilla.org/Web/Security/HTTP_strict_transport_security

CCleaner just lists them as Firefox cookies. I have no idea where they were or what type they are.

Is this article helpful in any way   -   in particular the section
'Third-party cookies'   ?

http://kb.mozillazine.org/Cookies

All cookies are turned off including third party cookies. The only cookies that can be modified are those already set for sites. Facebook is not among them.

I have tried directly blocking facebook cookies and domains to no avail. Firefox will NOT block social media cookies even if the sites are not visited or any of the 'like us on facebook' etc buttons are not used.

BTW, I am no newbie to firefox, or cookies. I have been using FF variants since netscape.

Two questions :
What's your response to cor-el's post   ?

Have you tried to contact Piriform   ?

https://www.piriform.com/contact/other-enquiry

Do you still get those cookies if you run Firefox in permanent Private Browsing mode (Always use Private Browsing mode; Never Remember History) as a test?

Permanent private browsing mode helps, no cookies appear in that mode. However visiting Google news or search seems to turn it OFF. More testing would be required.

CCleaner is just a browser cleaner and PC utility program. Follow that piriform link to learn more about it. I use it to clear cookies, history, etc. I also use it to clean up the registry. It is a good utility and has been for many years. They are not responsible for firefox allowing facebook cookies. Firefox itself should not allow cookies when they are turned OFF. Somehow cookies from facebook and twitter etc are still making it around the cookie exclusions built into firefox in normal browsing mode with cookies disabled.

http://cdn.polyfill.io/ is another tracking cookie system that is making it through also.

Hi Eric! I have a similar frustration with google.

Here is what I noticed: While a website is loading, on the lower left corner you can see very quick flashes of all the cr*p that piggibags onto the url before the website even appears. (This is what happens with Google, maybe because of google analytics websites use, I'm not sure.) I suspect that websites that have FB and other social media sites' sign-ins enabled on their websites might open themselves up to this kind of cookie behavior. I mean "share" buttons etc. You could try checking if the same thing happens with another site like Twitter. Block Twitter cookies etc and then go to a site that encourages sharing, and see if afterwards you have a Twitter cookie. Please post here again if this is the case, especially if you find a solution in blocking FB because I want to do the same thing to block Google. (By the way I have FB cookies appearing too without going to FB.)

I get twitter cookies also, just not as many. I have seen the flashing list at the lower left also. The facebook cookies don't seem to have any particular relationship to sites with facebook 'Like' buttons.

Private browsing is a pain because I have to login on every site I participate. Private browsing mode seems to work so why can't the regular firefox 'no cookies' mode work properly?

When Firefox starts up into an automatic private browsing session, cookies are only stored temporarily in memory and not stored to disk. So the main difference from a regular session is where cookies are stored, not which sites' cookies are stored.

I see you use the Cookie Monster extension. Can you use Cookie Monster to create a block for facebook.com? (Screenshot attached.)

The polyfill site probably is a cross-browser compatibility library used by some site you visit, but possibly one of your extensions. Extensions might not be bound by cookie preferences.

Thanks!

I will have to check and see if CCleaner can see those 'private -NOT' cookies in memory. That will be interesting. It seems like accepting cookies but putting them somewhere in Lymbo is still accepting tracking cookies.

I have tried using Cookie Monster to do just that but it did not seem to work. It is also hard to do for sites that don't show in the location bar. I will see if I can try that again though.

I think the polyfill comes from one particular site I visit.