Popupblocker is a free add-on for Chrome that effectively blocks pop-ups and prevents websites from opening new windows or tabs. This add-on is particularly useful when browsing websites that often open new windows with ads or when you accidentally click on a link that triggers a pop-up.

One of the standout features of Popupblocker is its "Smart" option, which intelligently detects and blocks unwanted tabs from opening. This means that only one new tab is allowed to open at a time, preventing websites from bombarding you with multiple tabs simultaneously.

What sets Popupblocker apart from other similar add-ons is that it is not easily detected by most websites as a pop-up blocker. It cleverly allows pop-ups to briefly appear before blocking them, ensuring that websites do not immediately recognize it as a pop-up blocker.

Overall, Popupblocker is a reliable and efficient tool for preventing annoying pop-ups and new tabs while browsing the web. Its "Smart" option and the ability to go unnoticed by websites make it a great choice for users looking for an effective pop-up blocking solution.