A lightweight and non-intrusive userscript that control video playback and set the preferred player size and playback quality on YouTube.
< Feedback on Yays! (Yet Another Youtube Script)
This can be disabled by clicking on the blue slide toggle above the related videos, or find the option in the settings menu.
Could we get a feature to disable YT new Autoplay?
What we can see at the top right: "When autoplay is enabled, a suggested video will automatically play next."