youtube-dl options
------------------

See https://www.mankier.com/1/youtube-dl#Options

Should always use:

--no-playlist  | only download a single video

Useful:

-x        | extract audio
-r 50k    | limit download rate

--max-filesize 1m | Do not download any videos larger than 1 MB

--no-mtime    | Do not use the Last-modified header to set the file modification time

--write-description   | Write video description to a .description file
--write-info-json     | Write video metadata to a .info.json file
--write-annotations   | Write video annotations to a .annotations.xml file
--write-thumbnail     | Write thumbnail image to disk

--print-json          | Be quiet and print the video information as JSON (video is still being downloaded)

--cache-dir x  | set permanent cache dir
--fmpeg-location x

--restrict-filenames  | Restrict filenames to only ASCII characters

-U   | update youtube-dl (may need extra permissions)

Not sure what these mean:

--no-post-overwrites