[Feature Request] Option to Write the End Screen JSON Code

[wertercatt]

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• Bug report (encountered problems with youtube-dl)
• Site support request (request for adding support for a new site)
• Feature request (request for a new functionality)
• Question
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The following sections concretize particular purposed issues, you can erase any section (the contents between triple ---) not applicable to your issue

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If the purpose of this issue is a site support request please provide all kinds of example URLs support for which should be included (replace following example URLs by yours):

• Video: https://www.youtube.com/watch?v=LcLQrxaHjm8
• Endscreen Data: https://www.youtube.com/get_endscreen?v=LcLQrxaHjm8

Note that youtube-dl does not support sites dedicated to copyright infringement. In order for site support request to be accepted all provided example URLs should not violate any copyrights.

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Description of your issue, suggested solution and other information

I would like an option that is like the already existing --write-annotations option. This option would write the data for YouTube's newish end screen system which was designed to replace the most common usage of annotations. Without being able to save this data, making a full archive of a YouTube video in its original form is no longer possible with youtube-dl. I've provided a link to the YouTube endpoint that contains this data in the previous section. Ideally when this option is used, an .endcard.json file containing the data from that endpoint for the downloaded video would be written.
I've attached a hypothetical example output (minus the video file for upload limit reasons) of the command youtube-dl -o '%(id)s.%(ext)s' --write-description --write-info-json --write-annotations --write-all-thumbnails --write-endcard https://www.youtube.com/watch?v=LcLQrxaHjm8 to help illustrate what I'm requesting.
LcLQrxaHjm8.zip