How could you implement multiple pages within the same browser tab without using iframes, embeds, objects, or a browser add-on in 2021?

So I want to be able to have a web page that is divided into different sections, each of those with a 3rd party web page open. If I use iframes or any similar technologies they are blocked by the 3rd party.

I also want to be authenticated to these web pages, ideally this being handled by my browser as it does already. One of the use cases I am thinking of is a news dashboard, with multiple news sites open at one time.

I don't want to use APIs I want to get the full page directly.

I’m totally stumped so any advice would be greatly appreciated!