Autoplay

When it is switched on, YouTube queues something up and plays it as soon as the current video finishes, showing what is coming next in the final seconds. Inside a playlist it plays the next item in that playlist. Outside one it plays a recommendation. The toggle sits on the player itself, at the top on mobile and at the bottom on desktop, and it defaults to off for accounts aged 13 to 17. Playback also stops on its own after a long stretch with no interaction. Do not confuse it with the muted preview clips that play as you hover on the home feed, which are a separate behaviour.