There are more preferences - not only with respect to the web browser - whose defaults should differ in a guest session compared to an ordinary session. Changing respective application for that reason would make little sense. In this particular case it can easily be done by modifying the guest session feature.
https://blueprints.launchpad.net/ubuntu/+spec/guest-session-sane- defaults ** Package changed: firefox (Ubuntu) => lightdm (Ubuntu) -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to lightdm in Ubuntu. https://bugs.launchpad.net/bugs/290507 Title: Firefox Should Not Prompt for Password Save in Guest Session Status in “lightdm” package in Ubuntu: Triaged Bug description: Binary package hint: ubuntu-desktop When using the guest session in Intrepid, Firefox prompts users if they want to save their passwords on websites. This is a problem for two reasons: 1. The passwords are only saved for that session (this is good, though a different impression is given by the offer to save passwords) 2. Alice logs in as a guest, saves a password in firefox, and then switches the session to Bob without logging out. Then Bob lets Joseph use the guest session by switching him to it, Joseph has access to the password that Alice saved previously. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/290507/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp