Alright, let's see:
AdBlock Plus
Add-on update checker
Classic Theme restorer
DownThemAll
eBay Sidebar
EverSync
Forecastfox (fix version)
Infonotary Configurator
Mega
Search Preview
signTextJS
Simple Currency Converter
Speed Dial FVD (of course)
Tab Mix Plus
TinyURL Generator
URLCorrector
Video DownloadHelper
X-notifier
Yet Another Smooth Scrolling

Come on, Fvdmedia, this is very old bug that occurs on all versions since 20 and any OS (I've seen in personally on Windows and OS X) and still hasn't been fixed. As a suggestion, why don't you replace that "chrome://fvd.speeddial/content/fvd_about_blank.html" with something that uses the internal URL system in Firefox like "about:FVDSpeedDial"?