How to change tabs?

Question

Google

More than once I came across such advertising when I clicked on which all my tabs were subordinated to the same site.
How so?
How can this thing be repeated?

Answer 1

The Google tag means Google yourself.
Okay, I'm kidding, I'm kidding. Bearded bug (by specification): window.opener contains a reference to the opening window. Full communication due to different origins will not work, but you can change the location.
PS All this is written for educational purposes. If I see you exploiting it, I'll kill it xD

Answer 2

I don't know about all tabs, but sites belonging to the same owner can be so specially coded (using the same websocket) that after opening a link, I take the current page to another (the logic can be any), i.e. after loading an open page via a link from the main one, the server is informed about this and sends a message to the main one (connects by session, sends codes in the link), after that the main one is reloaded.
I don’t understand the meaning of these actions and what benefit can be gained from this, but I personally observed this for a long time, only in one place - on a porn site.