I want to do something as follows... but is it possible on Firefox? 1. More than one person use same PC and browser. 2. If I sign in browser using my account, browser apply my setting and log in web services like twitter using my saved account and saved password automatically. 3. When I log out browser, browser logs out from web services and account and password are no longer saved and my colleague can't log in using my account. 4. If my colleague log in browser using his own account, browser apply his settings and log in web services using his account. At first, I thought that I can do this using Firefox account, but it seem different from what I imagined. If this is possible, would you tell me how to do?