On *Nix systems download youtube-dl and use provided app in this repo to download videos.
##### Mac OS/Linux Setup
To get downloading working do the following:
1. Check that the [file permissions](https://en.wikipedia.org/wiki/File_system_permissions) for "youtube-dl-bridge.py" include the `execute` permission.
2. Edit the "path" property of "web_video_dl.json" to point to the location of "youtube-dl-bridge.py" on your computer.
3. copy "web_video_dl.json" to the correct location on your computer. See [App manifest location ](https://developer.mozilla.org/en-US/Add-ons/WebExtensions/Native_manifests#Manifest_location) to find the correct location for your OS.