I want to make a YouTube video that I put in my second screen stay maximized while I go and do something in another window on my primary monitor.
Is this possible?
For everything other than VEVO (and certain copyright videos) you can use
youtube.com/v/VIDEO_ID this should bring it to 100% browser view area.
This is something that flash decides locally, not some setting on Youtube.
If you run windows this article over on Lifehacker tells you where to download a modified dll that will allow flash to remain full screen when it does not have focus.
Another option might be to use a html5 able browser (Chrome, Safari for example) and tell Youtube to use that to play video. According to this page Full-screen support is partially implemented
The same page also has a link to lets you join the html5 beta program.
I use VLC for that. It can even load playlists (might need some extra scripts for that to work). Also it skips advertisments.
Just press ctrl+n and enter youtube url.
You can download and install Flash Keep FullScreen from this website : http://flash-full-screen-multiple-monitor.clangen.com/
It will keep full screen for the video, even if they are paused or finished. It will also work for other applications in fullscreen, like Flash games on Facebook.
Very easy to use and install. I hope it helps.
I was looking after the same problem and found an awesome solution that works for all videos (VEVO as well).
Sign in to leanback, and it will give you a device code, which you can authorise by visiting
http://google.com/device. After the authorization is successful, you can browse all your videos in full screen.
Also, signing in is optional, and you can browse through videos normally.
Update for Firefox 13 and later:
about:config in the address bar to go to the Firefox configuration settings.
full-screen-api.exit-on-deactivate into the search bar and double click the resulting option to change it's value to false.