I can't seem to find any websites detailing the support for the iframe attribute "allowfullscreen". CanIUse.com doesn't seem to have a listing for it, for example.
Does anyone have the support information for Chrome, Safari, IE and Firefox?
I've started discovering some of my own answers:
FireFox: Added support in v18 (January 8, 2013) - Source
Chrome: Added support in v27 (May 22, 2013) - Source
Safari: Added support in v7 (October 22, 2013) - Source
Internet Explorer: Added support in v11
Microsoft Edge: Supported
It seems to be difficult to find detailed release notes for the other three, unfortunately.