Script Summary: Control autoplaying and playback quality on YouTube.

Version: 1.5.3

License: (CC) BY-SA-3.0 http://creativecommons.org/licenses/by-sa/3.0/

This userscript let you control autoplay and playback quality on YouTube.

The script uses the official YouTube Player API. That means, it works seamlessly and probably more reliably than other approaches.

Tested in Firefox 8.0.1, Opera 11.51, Chrome 16.0. Former versions of this script has been reported to work in Safari (with GreaseKit) by Polydactyl. You can also try this port by Pedro C Cavalcanti.

Manual

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

Quality

You can chose from 5 different options to set the video quality at page load:

AUTO: Let the player set the quality. (default)
LOW: Set the lowest possible quality.
MEDUM, HIGH: Set the quality to 480p, 720p max.
HIGHEST: Set the highest possible quality.

Auto play

You can control when to start playing the video:

ON: The video starts playing as soon as possible. (default)
OFF: The video starts when you click on the play button, or anywhere inside the video frame.
AUTO: The video starts playing when the page containing the player gets focus for the first time. This means, when you open a video on a new window, or a new tab, the video won't start until the page become visible. This feature is still in development.