Hi A Firefox profile stores all of your important data, such as your bookmarks, history, cookies, and passwords. If you've lost your Firefox settings, bookmarks, or saved passwords after updating or reinstalling, you might still be able to recover them from an old profile. This article explains how to locate your old Firefox profile and copy important data into your current one. [[Restore bookmarks, passwords and data from an old Firefox profile]] [[Recover user data missing after Firefox update]]