Context: All major web browsers allow the user to open multiple information resources at the same time, either in different browser windows or in different tabs of the same window. Major browsers also include pop-up blockers to prevent unwanted windows from "popping up" without the user's consent.

Question: What does not allow windows to pop up without consent?
Answer: pop-up blockers

Question: What do all pop-up blockers allow in a window?
Answer: Unanswerable

Question: What can be open without the user's consent in a window?
Answer: Unanswerable

Question: Where do unwanted windows open in a browser?
Answer: Unanswerable

Question: Where do browsers allow pop-ups to open?
Answer: Unanswerable

Question: What do information resources allow to pop-up in a window?
Answer: Unanswerable