Sadly I was forced to upgrade to Firefox 12 and it is crap! It removed all powers the user had. Example I was normally able to bock advertisement and never ever had to see a YouTube frame.
With the new Firefox 12 I can disable all the plug-ins but no joy. YouTube can still play and still shows its ugly spam head on each and every page there is. I am sick of it and is thinking just to get rid of the browser in its entirety
I even did the block command in my options tab. No joy. I had a look on Google followed the given instructions no joy. I also see I can no longer uninstall Shockwave Flash individually so am seriously considering just to do a format and install a version of Firefox that still is able to empower the user.
It is for this reason that I don't visit Threads with YouTube on it anymore. It takes forever to load and refresh. Not to mention how much data each of those frames eat...