In case you use "Clear history when Firefox closes" then check the settings. *do not clear the Browsing History *Options/Preferences -> Privacy -> Firefox will: "Use custom settings for history": [X] "Clear history when Firefox closes" -> Settings *https://support.mozilla.org/kb/remove-recent-browsing-search-and-download-history *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