Select some text, right-click and choose"Search image" in the menu, a Google Image tab will open with your results.
Dark YouTube theme - apply Black Youtube & Facebook Skin. Dark YouTube theme protects eyes by changing Youtube & FB colors to black
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.
Capture the whole page or any portion, annotate it with rectangles, circles, arrows, lines and text, blur sensitive info, one-click upload to share. And more!
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.
Reverse image search using various search engines, such as Google, Bing, Yandex, Baidu and TinEye.
Open and download links in IDM (Internet Download Manager) easily
The YouTube Mp3 Downloader Add-on includes a Button on any YouTube Page and allows you to convert the YouTube Video to a Mp3 with just one click. Compatible with new Firefox Quantum 57
Experience a beautiful image from Google Earth every time you open a new tab.
Allows user to block gif images on a web page.