Updated today (3-Mar) to firefox-28.0-b2+build1-0ubuntu2 (also installed all additional updates). Also installled lxde-common. Selected LXDE session from the lightdm screen. Firefox appears to be working properly in the LXDE session launched from lightdm, but crashes in the Lubuntu session launched from lightdm unless run as root.
Updated today (3-Mar) to firefox- 28.0-b2+ build1- 0ubuntu2 (also installed all additional updates). Also installled lxde-common. Selected LXDE session from the lightdm screen. Firefox appears to be working properly in the LXDE session launched from lightdm, but crashes in the Lubuntu session launched from lightdm unless run as root.