Firefox 16 won't start from the gnome shell in 12.10

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http://askubuntu.com – I've just upgraded to 12.10 and firefox doesn't work properly. When I start it from the gnome shell nothing happens, however system monitor shows me two processes called 'firefox', the last one of which has memory field as N/A. But when I just type in terminal firefox it starts and there is only one entity of firefox in the system monitor. (HowTos)