Firefox does allow you to keep certain cookies while deleting others. Here is how you can achieve it :

1. Go to top right corner and click on the hamburger option (three horizontal lines) 2. Select Options. 3. Head over to Privacy & Security option. (has a lock symbol) 4. Scroll down until you see "Cookies and Site Data". 5. Select the "Manage Exceptions" option. 6. You can specify which websites are always or never allowed to use cookies and site data. Type the exact address of the site you want to manage and then click Block, Allow for Session, or Allow.

Note that you shouldn't use "Clear history when Firefox closes" to clear Cookies and Site Preferences.

• clearing "Site Preferences" clears exceptions for cookies, images, pop-up windows, and software installation and exception for password and other website specific data
• clearing "Cookies" will remove all selected cookies including cookies with an allow exception you may want to keep

Hope it helps. If the solution works, please identify it as Solved, so that others with the same problem can get the solution too.

Note that you shouldn't use "Clear history when Firefox closes" to clear Cookies and Site Preferences.

• clearing "Site Preferences" clears exceptions for cookies, images, pop-up windows, and software installation and exception for password and other website specific data
• clearing "Cookies" will remove all selected cookies including cookies with an allow exception you may want to keep

les réponses de 2Bor!2B et de cor-el me paraissent contradictoires.(contradictory.)

Je voudrais un moyen simple (qui me paraît à la portée de la puissance de Firefox) pour conserver les cookies des sites qui m'intéressent, tout en éliminant systématiquement les autres à la fermeture.

I would like a simple way (which I think is within the grasp of the power of Firefox) to keep the cookies that interest me, while systematically eliminating the others when closing.

Let the cookies expire when Firefox is closed to make them session cookies instead of using "Clear history when Firefox closes" to clear all cookies including cookies with an allow exception you may want to keep.

• Options/Preferences -> Privacy & Security
  Cookies and Site Data: [ ] "Delete cookies and site data when Firefox is closed"

You can create a cookie allow exception with the proper protocol (https:// or http://)

You can set network.cookie.thirdparty.sessionOnly = true on the about:config page to make third-party cookies behave as session cookies that expire when Firefox is closed.

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

• https://support.mozilla.org/en-US/kb/about-config-editor-firefox

Je souhaite que Firefox MODIFIE son paramétrage des cookies de façon SIMPLE: -conservation des cookies sélectionnés par l'utilisateur -élimination des autres cookies à chaque fermeture.

I would like Firefox to SIMPLY MODIFY its cookie settings: -reservation of cookies selected by the user -elimination of other cookies at each closure.