This happens in all my browsers (some which doesn't have any extensions installed).
Why does this happen?
Best Answer
YouTube users can loop their videos by abusing the annotation system, specifically the pause function. If you turn off annotations when viewing the video, you will notice that it no longer loops.
If the video contains audio that may be subject to copyright, then the copyright holder has the ability to restrict playback in various ways. Some ways they do this could be the following:
Disabling audio on mobile devices
Disabling audio on any viewing platform
Disabling playback on mobile devices
Placing ads on the video
Blocking playback of video with a message saying the video had a copyright claim filed
Of course there may be a few other cases of things that they will do, but in this case the issue is most likely due to copyrights.
This problem is now fixed. I think it's probably a Youtube update as I haven't restarted Chrome as far as I can remember for maybe a week but I'm sure I've seen the problem within that time.
Best Answer
YouTube users can loop their videos by abusing the annotation system, specifically the pause function. If you turn off annotations when viewing the video, you will notice that it no longer loops.