When I try to play a video of any kind FireFox (55.0.2 64bit) errors out with the below message:
I have all the latest updates to Shock, Flash, etc.
If I try a Oracle VM and Windows 7 it still can not play it.
If I go to a Windows machine it plays fine.
I'm running 16.04 on a Lenovo G780.
I think this is something relatively new.
Thanks, Fred