It's more accurate to describe this as "Designed for everyone but IE". (IE is welcome to the party, but isn't interested yet.)
WebGL is new and there are a lot of issues being worked out right now, in the field, while we watch. As we move from getcontext("moz-webgl") to "experimental-webgl" to plain, old "webgl", these interop issues are slowly going away. In the mean time, lots of things are going to be broken along the way. Besides, if it all worked right out of the gate, that would mean they were not pushing far enough. ;)
WebGL is new and there are a lot of issues being worked out right now, in the field, while we watch. As we move from getcontext("moz-webgl") to "experimental-webgl" to plain, old "webgl", these interop issues are slowly going away. In the mean time, lots of things are going to be broken along the way. Besides, if it all worked right out of the gate, that would mean they were not pushing far enough. ;)