I had same problem and it was resolved by removing some plugins I had, leaving only flashplugin-alternative.so left in /usr/lib/mozilla/plugins/
sudo apt-get --purge remove totem-mozilla rhythmbox-mozilla
I had same problem and it was resolved by removing some plugins I had, leaving only flashplugin- alternative. so left in /usr/lib/ mozilla/ plugins/
sudo apt-get --purge remove totem-mozilla rhythmbox-mozilla