I have noticed that, also, compared with the IE9 and Avant. It's just that I have become so used to Firefox that I practically make it my primary browser. But I have also tried Chrome, which has its own Java plugin, and I found no problems with it.
Since my last post I also discovered something else with my Firefox, with respect to playing videos. To play videos on Yahoo News, I have to uncheck "Enable Javascript". However, to play videos on CNN News I have to check that box to Enable Javascript. To login to this site and send emails to those on my Yahoo Mail Contact List I have to enable Javascript. I don't have that problem with IE9 and Avant. The Avant browser is configured with videos, Active X, scripts, and Java applets enabled, unless you disable them, and I have mine set to IE Compatible.