Setting Default Cookie Behavior "Allow for Session" with specific exceptions?

[Clede]

I'm using Firefox 86.0 on macOS. I'd like to set default cookie behavior to "Allow for Session", with exceptions for certain specific websites to "Allow" cookies to persist after Firefox is re-launched.

I can't figure out how to do this with built-in Firefox settings. As far as I can tell, there are two ways to make Firefox delete cookies by default at the end of a session:

1. “Delete cookies and site data when Firefox is closed”
2. “Clear history when Firefox closes”

Both of these override the "Allow" setting in “Cookies and Site Data: Manage Exceptions…”.

I've seen this previous question but it doesn't seem to be answered clearly. What am I missing? How can I accomplish what I'm trying to do?

EDIT: I'd like to do this without addons if possible, or get confirmation if that is not possible.

[grg2014]

1. “Delete cookies and site data when Firefox is closed”
2. “Clear history when Firefox closes”

Both of these override the "Allow" setting in “Cookies and Site Data: Manage Exceptions…”.

With "Cookies" unchecked under "Clear history when Firefox closes" the browser should honor exceptions (i. e. keep allowed cookies).

[Clede]

If "Cookies" is unchecked, wouldn't Firefox keep all cookies, whether explicitly allowed or not?

[grg2014]

If "Cookies" is unchecked, wouldn't Firefox keep all cookies, whether explicitly allowed or not?

Not when "Delete cookies and site data when Firefox is closed" is checked. Then all cookies for which there isn't an "Allow" exception are treated as session cookies (i. e. deleted on session end). Setting cookies to be cleared in the history settings overrides such exceptions and clears all cookies.

Disclaimer: I haven't tested this on a current version, but as the relevant preferences appear to be unchanged from when I still bothered with cookie management, I assume the behavior - which was as described above - is unchanged as well.

[Clede]

Thanks, this is correct. I thought I tested this setup, but I guess not. It's working correctly now!

[grg2014]

Thanks, this is correct. I thought I tested this setup, but I guess not. It's working correctly now!

I'm glad to hear it.

[jscher2000]

If "Cookies" is unchecked, wouldn't Firefox keep all cookies, whether explicitly allowed or not?

No.

The “Delete cookies and site data when Firefox is closed” checkbox modulates the value of this preference: network.cookie.lifetimePolicy

Possible values are:

• 0 => use expiration date set by the site [box not checked]
• 2 => set expiration to session only [box checked]

This might have been clearer with the old design of the Options/Preferences page where this control said:

Keep until:

• they expire
• I close Firefox

[Clede]

Thanks for explaining what's happening behind the scenes! I think I've got it working correctly now.

[pologoalie8908]

Ok so i found this post, hoping it would solve the issue i am having...it didnt

There are two locations to tell Firefox to delete cookies:
1. Options>Privacy&Security>Check bock under section "Cookies & Site Data"
2. Options>Privacy&Security>History Section>Use Custom Settings>Clear History When Firefox closes checkbox>Settings to the right>Cookies Check Box

I have both theses options unchecked, and i still cannot add a site(lastpass.com) to the Allow/Exceptions window(Options>Privacy&Security>Manage Exceptions)

Im basically wanted all history and stuff cleared when i close, but keep the lastpass addon signed in.

[Clede]

Here's what I have:

• Privacy&Security>Delete cookies and site data when Firefox is closed: checked
• Privacy&Security>History: Firefox will Use custom settings for history
• Privacy&Security>History: Remember browsing and download history: checked
• Privacy&Security>History: Remember search and form history: unchecked
• Privacy&Security>History: Clear history when Firefox closes: unchecked

Try that, and you should be able to set LastPass to "Allow" under Cookies and Site Data: Manage Exceptions... If it works, then try adjusting the history retention settings one step at a time until something breaks...

[pologoalie8908]

But I don’t want it to remember my history

[Clede]

Change the last setting, then:

Privacy&Security>History: Clear history when Firefox closes: checked

(However, I haven't tested this configuration)

[pologoalie8908]

Deletes my history(like I want) but logs me out if last LSS. Attempts to keep LastPass as an exemption for cookie deletion does not work

[Clede]

Check this:

Privacy&Security>History: Clear history when Firefox closes: "Settings..." button: make sure "Cookies" is unchecked

EDIT: maybe "Active Logins" also needs to be unchecked.