[WhyNotHugo]

I'd love to see a toggle button on the URL bar for every website.

By default it's off, and it means that cookies as deleted as soon as I close the last tab for that website.

Clicking it whitelists the website and cookies are retained until I turn it off again.

This is kind of like the approach we had in the nineties. You used to get a prompt for each website, asking if you wanted to allow cookies or not. This is like a second iteration on that.

[bostonvaulter2]

This is pretty much exactly what Cookie AutoDelete does. I love it. Although there's a Firefox bug currently that's preventing many cookies from being deleted which has been annoying, but should hopefully be resolved soon.