quinns
commented
7 years ago I don't think it actually is. Make sure you have "Disable Cache (while DevTools is open)" checkbox disabled in the Network tab. This should cause your browser to not re-download the video for each loop, and better mimics real-world behavior.
Vide doesn't do anything to prevent endless cycle of download and streaming to a small video file. I'm looping a 30mb file but this browser has downloaded over 5x that in just a few mins of having the page up in my browser.