A lightweight and non-intrusive userscript that control autoplaying and set the preferred player size and playback quality on YouTube.

The script uses the official YouTube Player API, which means, it works seamlessly and is probably more stable than other solutions.

Tested in Firefox 19.0.2, Opera 12.11, Chrome 23.0.

Manual

A new button with a "cogwheel" icon will appear below the video player. When you click the button, a panel will show up with three options:

Quality

You can choose your preferred playback quality which is set automatically when page loaded. Beside the standard resolutions (240p, 360p, 480p, 720p, 1080p) there are two special options:

AUTO: Let the player choose the proper quality. (default)
ORIGINAL: Set the highest available quality.

Size

You can set the default player size to:

AUTO: Let YouTube handle the player size. (default)
WIDE: Set the wide size as the default.
FIT: Set the player width the same as the page width, keeping the aspect ratio.

Auto play

You can control when the player starts playing the video:

ON: The video starts as soon as possible. (default)
OFF: The video is paused by default.
AUTO: The video starts when the page gets focus the first time. This means, when you open a video in a background tab, the video won't start until the tab become visible.

Translations

English, Hungarian, Dutch (by Mike-RaWare), Spanish (by yonane), German (by xemino), Portuguese (by Pitukinha), Greek (by TastyTeo), French (by eXa), Slovenian (by Paranoia.Com), Russian (by an1k3y), Hebrew (by baryoni), Chinese (by blankhang), Polish (by mkvs), Swedish (by eson)

Related

GitHub repository
Userscripts.org page
Gresemonkey for Firefox
Tampermonkey for Google Chrome

Source

Changelog