Reverse image search using various search engines, such as Google, Bing, Yandex, Baidu and TinEye.
YouTube High Definition is a powerful tool that will let you automatically play all YouTube videos in HD (High Definition), turn off annotations, change video player size, auto stop videos, auto mute videos, control embedded videos and much more.
Enlarge thumbnails, and show images/videos from links with a mouse hover.
Easily download most popular video formats.
瞬间过滤B站(bilibili.com)刷屏的相似弹幕，还你清爽的弹幕视频体验。 *a tweak for a Chinese website. Please ignore this add-on if you are not a user of bilibili.com.*
Tons of features to improve your user experience on YouTube™.
Stops video autoplay and shows the preview thumbnail.
The entire page will be fading to dark, so you can watch the videos as if you were in the cinema. Works for YouTube™ and Beyond. It works for all known video sites such as YouTube, Vimeo, Twitch, Dailymotion, Facebook, Hulu, Metacafe, YouKu, etc.
Make view image button great again. This web extension adds "View Image" button to Google Image Search results.
Open and download links in IDM (Internet Download Manager) easily
Vid to Mp3 is fast Firefox Addon for Downloading Youtube Videos and Convert to Mp3/Mp4/AVI/3GP and other audio/video format.
Just One Click to download any video from Youtube. Support new Firefox Quantum 57