OT: Can;'t find a Mozilla user group

[Anthra Norell]

I can't run Firefox and Thunderbird without getting these upgrade 
ordering windows. I don't touch them, because I have reason to suspect 
that they are some (Russian) virus that hijacks my traffic. Occasionally 
one of these window pops up the very moment I hit a key and next a 
confirmation message appears "reassuring" me that the upgrade will be 
installed the next time I start. I meant to ask Mozilla about their 
upgrade policy and facilities but for all the googling I do I can't find 
a contact address, nor an active user group. Hints will be greatly 
appreciated. Thanks!

Frederic