Video Closer by Marabunta

Video Closer (formerly YouTube Closer) turns your open tabs into a video queue: open several videos in their own tabs and sit back.

Supported platforms:
• YouTube
• Vimeo
• Dailymotion
• Twitch (recorded videos)

Features:
• Automatic closing: as soon as a video ends, its tab is closed – optionally after a configurable countdown.
• Seamless continuation: the next open video tab starts playing automatically – with or without switching focus, your choice.
• Per-site control: every platform can be enabled or disabled individually in the settings.
• Playlist protection: YouTube tabs with a list= parameter are left alone, so playlists and mixes keep playing.
• Lightweight & private: no tracking, no unnecessary permissions – just tabs and storage.

Note: to let the next video start in a background tab, allow autoplay for the site (padlock icon in the address bar → Autoplay → "Allow Audio and Video"). Otherwise the video starts when you open its tab.