It disables autoplay and enables click to play.
目前為
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How to install UserScripts:
https://greasyfork.org/en/help/installing-user-scripts
Functions of this script:
It displays thumbnail images instead of auto-playing videos on channel pages, individual video pages, etc.
You can play the thumbnail videos by mouse click or [Space] key.
Advertisements, live streamings and videos on the playlist would automatically start normally.

Try on YouTube:
https://www.youtube.com/
My YouTube Scripts:
https://greasyfork.org/en/scripts?set=361295
Twitter:
@kantankikaku
#YouTubeClickToPlay
Keywords:
kill prevent avoid disable turn off autoplay autostart auto automatically play start
channel home top user video page show thumbnail poster cover image
force enable require need have to click tap touch space key settings preferences configs option