So after a few tries I did manage to screen capture EMF with ffmpeg.
So, I hacked it ... I was wrong ...
Same as Flash, you can make pretty good screen captures. What remains to be seen is if the simple addons using the browser's cache to save the stream -- with encrypted flash they cannot [along with EMF encryption (speculated)].
There were some ffmpg updates recently so that my be the reason of the stream x-11 grab failure a few weeks ago maybe?
So, The Motion Picture Association of America (MPAA) just ''shit a brick''