Not just Youtube, but I'm experiencing this problem aswell with Veoh.com. I play the movies fine, but if I try to full screen it, I can only hear audio and cannot see anything but a black screen. I thought that this might have been associated with me changing player defaults when I installed iTunes, but I have since uninstalled iTunes and nothing. Help?
I checked 5 different systems here (3 ThinkPads, 1 3000 series and an HP). Only one of them has a problem viewing youtube fullscreen, and that one had a failed iTunes installation on it. Don't know if that helps or not.
ThinkPad Slate, T410s, X301, X200 Tablet, T60p, HP TouchPad, iPad 4, iPhone 4S, IdeaTab A2107A I am not a Lenovo Employee. If you find a post helpful and it answers your question, please mark it as an "Accepted Solution"!
I actually haven't tried it yet with my IE, but I've installed and uninstalled iTunes and Quicktime and my fullscreen doesn't work. This saddens me, as it used to work before I decided to install iTunes just a couple days ago. I am pretty bummed.
See the thing is, the other night was the first time I've used IE to look up Youtubes. So when I was on Youtube, I had to install a fresh plugin. That didn't work still. However, I'll be sure to try different combinations of removing iTunes and Quicktime, cleaning registries, and reinstalling the flash plugins.