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Firefox set to clear cookies, yet

  • 5 replies
  • 1 has this problem
  • 17 views
  • Last reply by Blenheim

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I have Firefox set never to remember cookies except for a few select sites and to erase cookies and internet history upon closing the browser. Indeed, the sites outside my whitelist have always acted as if cookies are disabled for them (giving "you must enable cookies" if I attempt to log in, etc.). I also am required to re-log in to whitelisted sites after relaunching the browser, of course.

However, I just ran CCleaner, and its deletion log listed over 1400 Firefox cookies, a great many from sites I haven't visited in months. Apparently, Firefox's "never store cookies" option either isn't working due to a glitch or just doesn't work period, appearing to the user not to store cookies but just storing and not deleting them anyway.

1. Does Firefox just save cookies anyhow no matter your preferences, or is this a glitch? If it is a glitch, how do I resolve it? 2. Where is the age-old cookie information that CCleaner deleted stored, so I can delete it manually in the future?

(Note: Yes, I know about CCleaner's privacy concerns, but that's beside this particular point.)

Thanks in advance for any help.

I have Firefox set never to remember cookies except for a few select sites and to erase cookies and internet history upon closing the browser. Indeed, the sites outside my whitelist have always acted as if cookies are disabled for them (giving "you must enable cookies" if I attempt to log in, etc.). I also am required to re-log in to whitelisted sites after relaunching the browser, of course. However, I just ran CCleaner, and its deletion log listed over 1400 Firefox cookies, a great many from sites I haven't visited in months. Apparently, Firefox's "never store cookies" option either isn't working due to a glitch or just doesn't work period, appearing to the user not to store cookies but just storing and not deleting them anyway. 1. Does Firefox just save cookies anyhow no matter your preferences, or is this a glitch? If it is a glitch, how do I resolve it? 2. Where is the age-old cookie information that CCleaner deleted stored, so I can delete it manually in the future? (Note: Yes, I know about CCleaner's privacy concerns, but that's beside this particular point.) Thanks in advance for any help.

Chosen solution

Your Firefox identified itself as version 55. Is that correct? You can verify your current version on the Troubleshooting Information page. Either:

  • "3-bar" menu button > "?" Help > Troubleshooting Information
  • (menu bar) Help > Troubleshooting Information
  • type or paste about:support in the address bar and press Enter

In the first table on the page, you should find a row with the version number.

If it's 60.something in the esr series or 62.something, your user agent may need to be reset. See: How to reset the default user agent on Firefox.

If it's not one of those versions, see: Update Firefox to the latest release.


Some versions of CCleaner may treat HSTS data in the SiteSecurityServiceState.txt file as "cookies" even though they are not cookies. Check with Piriform if this does not explain the discrepancy.

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All Replies (5)

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Chosen Solution

Your Firefox identified itself as version 55. Is that correct? You can verify your current version on the Troubleshooting Information page. Either:

  • "3-bar" menu button > "?" Help > Troubleshooting Information
  • (menu bar) Help > Troubleshooting Information
  • type or paste about:support in the address bar and press Enter

In the first table on the page, you should find a row with the version number.

If it's 60.something in the esr series or 62.something, your user agent may need to be reset. See: How to reset the default user agent on Firefox.

If it's not one of those versions, see: Update Firefox to the latest release.


Some versions of CCleaner may treat HSTS data in the SiteSecurityServiceState.txt file as "cookies" even though they are not cookies. Check with Piriform if this does not explain the discrepancy.

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Hello, Answering yes to the site permissions asking you allowed these cookies! They are kept until they expire. If you want to navigate smoothly and secure accept cookies and keep it until Firefox is closed. Hope this help

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jscher2000,

You were correct about the SiteSecurityServiceState.txt file; the HSTS supercookies were what was being detected. I deleted the file and replaced it with a read-only copy, which seems to have solved the problem. CCleaner is now habitually picking up three new files in the cache2 folder, but the content of those seems to be purged each session as per settings, so I seem to be good to go. I wasn't aware that Firefox had this big problem, and it took a bit of sleuthing to fix it manually, but I appreciate that you identified the problem.

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The SiteSecurityServiceState.txt file doesn't store cookies, but stores security data about whether to access websites only via a secure connection. You should leave 5his file as it is and not prevent Firefox from creating it. If you have a problem with this file ann CCleaner then you should contact its developer for support.

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cor-el said

The SiteSecurityServiceState.txt file doesn't store cookies, but stores security data about whether to access websites only via a secure connection. You should leave 5his file as it is and not prevent Firefox from creating it.

Sources disagree on that, and even if no cookies are involved, the file still amounts to a master list of every site I've visited. It's not like I'm going anywhere horrible, but the file was doing something I specifically asked Firefox not to do through the History settings. I gotta leave the read-only version in place.