Why does a video start playing when I hover over a thumbnail, and how can I turn this off?

In subtitle search, hovering over a thumbnail can load a YouTube iframe and start playback at the first matching caption. Moving the pointer away before playback begins cancels the preview. Hover autoplay is currently enabled by default.

To disable it, use the Autoplay switch on the subtitle results page, or open Settings, set Autoplay videos on mouse-over to No and save. You can still click a thumbnail to play the video.

Loading a YouTube iframe may allow YouTube to receive technical information about your browser and visit under its own privacy practices. Disabling hover autoplay prevents automatic video previews. On metadata search, unlisted search, channel pages and My Notes, clicking a thumbnail opens a floating window with the player inside the iframe.