YouTube™ is a video-sharing website owned by Google, Inc. It enables users to watch, upload, and share videos.

When you're watching a video on YouTube, you can add a repeat button in the HTML5 player and get a seamless repeat over a single track. This allows you to play the video and then pause it and listen to it again.

It's compatible with the latest versions of Firefox and Chrome for desktop, but only with the version of the YouTube player used by the website.

YouTube doesn't offer a similar extension, so if you want to repeat a track, you will need to add it to the video.