You don't even need HTML. Encoded as an mp4 with ffmpeg -movflags +faststart and you now have a mp4 that almost all browsers can use the seek bar within without

You don't even need HTML. Encoded as an mp4 with ffmpeg -movflags +faststart and you now have a mp4 that almost all browsers can use the seek bar within without any sort of javascript or HTML. Streaming without all the complexity of 'streaming'. Just a simple static .mp4 file on a webserver.