it's safeIf someone can confirm this is safe and or link to a better one it would be very appreciated. Having Youtube videos while in an area without internet would be very nice.
youtube, as well as some other video sites, often use the Opus audio format, and sometimes that is the best quality audio the video has. But Opus audio will not go into a mp4 file, so it creates a mkv file. This is a less compatible, less understood format not suited for the boomer mind, which is why I have set it to download the best mp4-compatible formats. This is not youtube-dl's default behavior.What I posted
I.e. you'll get bestvideo+bestaudio downloaded separately by default and muxed into a single file, or alternatively you'll get the best single muxed file. Which is what you're telling youtube-dl to do with this
-f bestvideo[ext=mp4]+bestaudio[ext=m4a]/mp4 --merge-output-format mp4
When I tried to do it, Kiwi Farms rejected the 360p file as too big, and the other low resolution files as 'not video'. It also rejected .m4a. So I ended up transcoding m4a to mp3. It's not like there was much of interest in the video anyway.