ExtendTube

This extension extends YouTube player capabilities. It will add few buttons on page that will allow you to: loop video playback (whole or selected part), seek video back or forward, step one frame forward, download video, choose default video quality... You can also control video via keyboard shortcuts or extension pop-up. FEATURES (almost all can be configured): — hide ads on page — hide in-video ads — disable autoplay — loop video (or selected part) — force video quality — enable wide player — autohide video controls — hide video annotations — download video (SD, HD, 3D, WebM, Mobile) — download just audio (MP3) - see help — load lyrics for video (from lyrics.wikia.com) — convert thumbnails to videos — show video ratings above thumbnails — keyboard shortcuts — hide some parts of page — change page colours — change player theme — add custom CSS — add custom JavaScript — detect videos embedded in other sites (only via iframe) — watch HTML 5 videos in full screen (F11) - see help