yt-dlp (download videos from youtube) yt-dlp is a youtube-dl fork based on the now inactive youtube-dlc. The main focus of this project is adding new features and patches while also keeping up to date with the original project. yt-dlp has several optional runtime dependencies, which aren't required for most common use cases. They don't have to be installed before yt-dlp is built, and can be installed after yt-dlp (which won't need a rebuild). mutagen: Required for embedding thumbnails in mp4 files (the --embed-thumbnail option). phantomjs: Used in extractors where JavaScript needs to be run. It's not clear to the SlackBuild author which content providers need this; YouTube does not. python3-websockets: Required for downloading over WebSocket ("ws://" and "wss://" URLs). If you've never heard of the WebSocket protocol, you probably don't need this. pycryptodomex: For decrypting AES-128 HLS streams and various other data. It's not clear to the SlackBuild author what content providers use AES-128. YouTube does not, that I've ever seen. secretstorage: For --cookies-from-browser to access the Gnome keyring while decrypting cookies of Chromium-based browsers on Linux. xattr: For the --xattrs and --xattr-set-filesize option. If you do not have the necessary dependencies for a task you are attempting, yt-dlp will warn you. All the currently available dependencies are visible at the top of the --verbose output.