There is also https://chrome.google.com/webstore/detail/enhancer-for-youtube/ponfpcnoihfmfllpaingbgckeeldkhle https://chrome.google.com/webstore/detail/enhance

There is also https://chrome.google.com/webstore/detail/enhancer-for-youtube/ponfpcnoihfmfllpaingbgckeeldkhle https://chrome.google.com/webstore/detail/enhancer-for-youtu... - you can tweak several things by one extension