This plugin is a bookmarklet. A bookmarklet is a tiny program stored inside a browser bookmark, and it's typically executed by clicking a button in the browser's bookmarks/favorites toolbar. If you are unfamiliar with bookmarklets, please see the corresponding documentation for the Firefox and Chrome browsers.
To install bookmarklet, drag this text link to your browser's bookmarks/favorites toolbar: Convert Video!
The bookmarklet has been tested in the latest versions of Firefox and Chrome. It may work in other browsers as well. That said, the plugin has not been heavily tested in other browsers, and thus support in other browsers may be limited.
You may need to enable or "unhide" the bookmarks/favorites toolbar in your browser. Some browsers do not have it enabled by default.
Additionally, if you are having trouble getting the plugin to work, then you can try initiating a "private" browser session first before using it. Please see the corresponding Firefox and Chrome documentation for instructions on how to achieve this.
To use bookmarklet, navigate to a YouTube, Dailymotion, Vimeo, Metacafe, VK, SoundCloud, Instagram, AOL, Vevo, or GoogleDrive video/audio page, click the bookmarklet in your browser's bookmarks/favorites toolbar to launch the plugin, choose a file type, and then press the "Go!" button. A new tab will open in your browser where the video/audio will automatically be converted on our site!