YouTube auto Pause and Resume by James Fray

This extension does not add any UI element and uses no resource at all. Only on YouTube pages, a very tiny script is injected which controls the player's playing status based on document visibility status. When a YouTube tab is brought to the front, the player automatically resumes exactly like pressing the play button and when the document is hidden, the player will automatically pause exactly like when the pause button is pressed.

For FAQs and other useful YouTube enhancer extensions please visit:
http://add0n.com/youtube-tools.html?from=auto-pause

Change Log:
0.1.1: It is possible to disable and re-enable the extension from the toolbar button. This is useful when you want to listen to YouTube videos in a background tab.

--- My YouTube Enhancer Tools

• YouTube use Flash Player
• YouTube in HD (720p, 1080p, 1440p, 2160p)
• YouTube no Annotations
• YouTube no Buffer (no autoplay)
• YouTube Stop AutoPlay Next
• YouTube toggle Flash and HTML
• YouTube Player AdBlocker
• YouTube auto Pause and Resume
• YouTube™ Stop Button
• Theater Mode for YouTube (YouTube Wide Screen)
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Please note that the FAQs page of this extension contains Google Analytics; Terms can be found https://www.google.com/analytics/terms/