I have no direct solution to you exact problem but your usage of tabs sounds like a nightmare.
A while back I found Omnivore which works like a charm if you want to "freeze" the contents of a website to read them later. You can also self host it if you like.
I took it a step further because I love Obsidian as personal knowledge management and I want to have everything in one place. There's a plugin to sync all your saved pages from Omnivore to Obsidian. In the template for it I then have my marked highlights, the links to the version in Omnivore and the original URL and also the whole content. So I have all of that in markdown which is really nice to work with.
Maybe that's a solution you too could be happy with.
Unfortunately, the switch from YouTube to PeerTube has not worked for me so far. I can't find a decent instance (not full of right-wing/conspiracy content) with interesting stuff that also allows me to make an account.