Video Blocker allows you to hide videos from channels that you don't like. You can specify these channels by right-clicking on a link to a video on YouTube or by adding them manually via the options page. You can also hide videos from multiple channels at once, by using a wildcard. Blocking videos with certain keywords in their title is also possible! For more information on how to do this exactly, please visit the help section after installing this extension.
Good luck and happy video blocking!
This extension is also available for other browsers!
Google Chrome: https://chrome.google.com/webstore/detail/video-blocker/jknkjnpcbbgcbdbaampbjlhkcghmgfhk