Some optimized mp4 do not play at all in any of my FF. From what I can see, this video is 10 fps and description says "Optimized using ezgif.com". Small and short videos.… (read more)
Some optimized mp4 do not play at all in any of my FF. From what I can see, this video is 10 fps and description says "Optimized using ezgif.com". Small and short videos. Lenghts seems to be correctly indicated by FF player frame.
All other MP4 play perfectly in any of my FFs. When I download such mp4 to my computer, VLC will play it normally. Any FF at this same computer will not! I repeat: all other videos play perfectly normal, including any MP4 I tried! Anything else on this same site plays normally. I am on Win 7.
I remove all security features I can, still, this single sort of videos are not playing and this is true for any such videos on this site. I tried 4 different versions of FF (v29, 60.9.0esr, v65 IceDragon, v71). They inherit configuration from the existing ones, so they are not clean installs. The same problem I have in several Win7 computers (two Virtual Machines and a real computer, not Win 7 N). FF safe mode does not help also.
Example page containing such mp4 with a cat: https://www.index.hr/lajk/poster/227148/vlasnici-su-snimili-svoju-smijesnu-macku-koja-se-moze-provuci-i-kroz-najmanji-prostor
and when I isolate just the video:
in FF I get only an empty black page and frame with player and no video at all.
What is wrong here?