Since update to 3.6.12 on my Ubuntu 10.10 system, streaming media sites do not function properly anymore.
Previous to the 3.6.12 update I was able to stream a variety of types of videos, but after the upgrade, none seem to function properly. Specifically YouTube.com does not work, it will start to load and then hang. Sometimes causing the whole firefox process to become unresponsive and I have to kill it. Also, certain ads on websites are not displaying properly (flashing super fast like a strobe), some embedded videos don't display at all, and various mixed-media types of websites hang and cause Firefox to lock up. Everything is working as normal within Chrome... I've reinstalled my flash plugins, without any change. It seems to be specific to 3.6.12.