User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:5.0) Gecko/20100101 Firefox/5.0 Build ID: 20110622232440 Steps to reproduce: Environment: I'm using Firefox 5 on a Ubuntu 10.10 system. To ensure that there is no side effect with some add-ons a new user profile was created and the behaviour was verified. What was done: - Starting Firefox - Enable "Privacy -> Clear history when Firefox closes" - Creating an AppTab - Restarting Firefox Actual results: The App Tab was disappear. Expected results: The App Tab shouldn't disappear. A workaround for this problem is: Disable "Privacy -> Clear history when Firefox closes -> Settings ... -> Browsing History" There should be an option Clear Browsing history without killing the app tabs, if this Is this the desired behaviour.