Sharing only because it's relevant, I built this for myself. It uses your browser's cookies/sessions to find stuff you liked and favorited, and downloads it locally using yt-dlp and a sqlite database.

It works really well! And it's all free, open source, and built with Rust to make the footprint as small as possible.

It also has a cool TV mode where you can pick a channel (tiktok/youtube/instagram) and it autoplays stuff at random, even has cool "tandas" videos for in-between to make it feel more authentic. Check it out!

https://github.com/sergiotapia/joyscroller