Record failed downloads

[SebiderSushi]

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Description of your issue, suggested solution and other information

I often use youtube-dl to download playlists from YouTube in the background. Sometimes there are download errors or the video is unavailable due to copyright etc.
In those cases it's quite unpractical to skim through youtube-dl command line output from hundreds of videos and I also don't want youtube-dl to abort on these errors but rather download the available videos instead.
However I would also like to know that there are failed downloads and I'd also like to know the reason.
I tried redirecting stderr to a file but there are many other errors ending up there too and if a download fails the error messages are completely out of context because the video ID isn't repeated to stderr...

Is there any existing way to record failed downloads along with their reason of failure and video ID that i overlooked?
If not, I'd be really grateful for a new feature that could record just about this information to a given file - similar to the download archive - containing platforms, IDs and error messages for failed downloads.

[SebiderSushi]

bump

[RomeSilvanus]

I support this too. An option where it writes into the download archive, even when the actual video is not available (e.g.: blocked, deleted) would be nice to have.
I have some scripts that check channels periodically and checks against the download archive. And while I could do some script stuff around it, it would be nicer to have it built-in.

[Kaos-Industries]

As a user of the tool for years who plans to start using it to back up my huge YouTube playlists, this feels like a feature the program should have had some time ago. The entire reason it's necessary to backup my YouTube playlists is because they have such high attrition rates, with videos constantly being yanked off YouTube by copyright holders or uploaders deleting their accounts.

It's that very unpredictably in a playlist that ironically currently makes it impossible for me to set youtube-dl to run via crontab on 1000-video playlists and trust that it'll intelligently skip over and log the videos that couldn't be reached. It's desperately needed, and unlike @RomeSilvanus, I don't have the skills to script such a feature myself.

[ajh0912]

Would love to see error logging in youtube-dl. I archive 300 YouTube channels, there are just too many failed downloads to be able to manually make a list of videos that I need to try to download via other methods or by tweaking youtube-dl options. For example videos that require payment, are region locked, have age verification etc.

It'd be great to see something like the following:
An option "--error-log" where you then specify the destination output file like how "--download-archive" works. It logs the failed video IDs line by line like the download archive does for downloaded videos.

Another option "--error-log-verbose" where it stores each video ID and follows it with the verbose error output that gives context into each video's error.