Hi, the "Delete cookies and site data when Firefox is closed" checkbox instructs Firefox to shorten the expiration time for all cookies to the current session ("Allow for Session"). You can make exceptions for sites where you want to stay logged in. In that same section is the Manage Permissions/Manage Exceptions dialog. There you can see which sites you've exempted from session-only cookies and you can add new ones. An easier way to create an exception is using the Page Info dialog. While you are on the relevant page, you can call that up using either: * Command+i (for Windows, Ctrl+i) * right-click a blank area of the page > View Page Info * (menu bar) Tools > Page Info When the dialog comes up, click the Permission icon at the top to show that panel. Scroll down to "Set Cookies" and uncheck the "Use default" box, and then select '''Allow''' to let the site set persistent cookies. ''There's no Save button, you can close the dialog now.'' Finally, it's possible to set Firefox to erase all of your cookies and your exception list every time you close it. To make sure that's not going to happen, scroll a bit further down on the Preferences page to the History section. Set: Firefox will: Use custom settings for history and make sure these are '''not''' selected: * "Always use private browsing mode" => doesn't save site-specific information * "Clear history when Firefox closes" => can remove not just cookies but also exceptions; if you want to use it, click the Settings button to the right and remove the check marks from categories you do not want erased