more notes:
I just used youtube-dl to download your video, and I got a 1920x1080 file, encoded with hevc / h265, 14" long.
I’m a bit ignorant about this, and I expected h265 to be currently well supported by main web browers but…it looks that’s not the case at all. Compare
HEVC/H.265 video format | Can I use... Support tables for HTML5, CSS3, etc vs. "h264" | Can I use... Support tables for HTML5, CSS3, etc
I’d suggest you try again encoding in h264.
Check out our thread about ffmpeg. There’s an entry about h264 there. Also, we may want to update it with some notes about h265 support…