Support for downloading Facebook Stories

[jdunn0]

Checklist

• I'm reporting a site feature request
• I've verified that I'm running youtube-dl version 2019.07.16
• I've searched the bugtracker for similar site feature requests including closed ones

Description

I would like support for downloading Facebook Stories in youtube-dl.

Facebook Stories are similar to Snapchat, in that you create a video that stays up for 24 hours and is then deleted (though by default Facebook will archive your own stories so you can see them after that but no one else can).

[jdunn0]

I created a public Facebook Story that can be seen here.

I used the Chromium Inspect tool to find the video element.
It says the XPath of the video element is //*[@id="xt_uniq_1"]/div[2]/div[1]/div/video so it seems Facebook sticks the video element under a few other elements in the source code.

The video element source is here.

It would appear that the video URL points to an MP4 file.

Facebook Stories are either a picture or a video depending on the options you select, I'm only really interested in downloading the videos anyway and it seems possible to add support for that to youtube-dl to make things easier then using the Chromium inspect tool each time I want to download a video though it would need to login with Facebook somehow to access all the non-public story videos so that could be tricky.