Greasy Fork is available in English.
Watch videos from video sharing websites without Flash Player.
What exactly do you mean with auto buffer? Buffering is handled by the used playback plugin (resp. the browser if you use HTML5). If you are using Linux try gecko-mediaplayer or vlc. VLC does also work with Windows but you can not use the vlc-plugin with a proxy under Windows.
[Request] Auto Buffer
Only thing missing from this great plugin, thank you.