Primarily, this is determined by your Firefox privacy settings. You want to make sure that you are not blocking cookies from the websites that you are logging into (this includes in the '''Clear history when Firefox closes''' option). If you do use the '''Clear history when Firefox closes''' option, you want to ensure that you don't clear the '''Active Logins'''. You should also ensure that the '''Delete cookies and site data when Firefox is closed''' option is disabled in your settings. Also, for your [[Content blocking]] settings, you will want to ensure that you are not blocking cookies. If you are using the '''Strict''' setting, this may prevent you for staying logged in. It's also important to note that not every website will allow you to stay logged in. Some websites may require you to check the '''Remember me''' option in order to remain logged in between sessions. Hope this helps.