Cortesemente potresti fornirci ulteriori ragguagli in merito alla tua configurazione?
http://forum.mozillaitalia.org/index.php?topic=41179.0
In Safe Mode il problema è lo stesso?
windows 8.1
kaspersky 16.0.0.614
firefox 42.0
Ace Stream Web Extension 1.0.2 true acewebextension_unlisted@acestream.org
Adblock Plus 2.7.2 true {d10d0bf8-f5b5-c8b4-a8b2-2b9879e08c5d}
AS Magic Player 1.1.42 true magicplayer_unlisted@acestream.org
Classic Theme Restorer 1.4.9 true ClassicThemeRestorer@ArisT2Noia4dev
FEBE 8.8.1 true {4BBDD651-70CF-4821-84F8-2B918CF89CA3}
Gestione sessioni 0.8.1.12 true {1280606b-2510-4fe0-97ef-9b5a22eafe30}
Kaspersky Protection 4.6.2.31 true light_plugin_D772DC8D6FAF43A29B25C4EBAA5AD1DE@kaspersky.com
Modern Download Manager 0.2.1.1-signed true modernDownloadManager@teo.pl
RoboForm Toolbar for Firefox 7.9.11.1 true {22119944-ED35-4ab1-910B-E619EA06A115}
Tab Mix Plus 0.4.2.2 true {dc572301-7619-498c-a57d-39143191b318}
Undo Closed Tabs Button 3.9.9 true undoclosedtabsbutton@supernova00.biz
Adobe Acrobat - Create PDF 2.0 false web2pdfextension@web2pdf.adobedotcom
Logitech SetPoint 6.5 false {F003DA68-8256-4b37-A6C4-350FA04494DF}