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There’s an issue with an Alpha/Beta Release of Ubuntu, what should I do?
caution: 12.10 is not yet released but I was told it will say as is also when release happens (live session)
So, new ubuntu live session does not have option to "logout" and choose different desktop environment (DE).
This function was usable if one installs ubuntu live on USB stick with permanent changes. One can install any software, including KDE (plasma) or LXDE. Until including 12.04, one could simply logout and choose different DE.
Now, there is no "logout" option in top right menu and if ran service lightdm restart
it automatically logs in to live session account with unity.