On my Dell Inspiron 15, Intel Core i5 installed with openSUSE 13.2, I cannot play any video in any of my above mentioned browsers. I have smplayer version 14.9.0 installed and firefox applications such as mp4 and so on have been set to use this application. But every time that I attempt to play a video in the browser, the message appears: "An error occurred. Try again later. Learn More. But this gives no help. Guidance would be most welcome.
afaik Firefox uses the operating systems build-in codecs to do video decoding, you need the non-free codecs from packman for mp4 support.
read the info from hcvv’s link