This extension is for anyone, who uses websites with pop-up ads (ads that open in a new tab). red icon -> TabBlock prevents opening any new tab. green icon -> TabBlock allows opening new tabs freely. Note! Redirections to ads in the same tab still work! You can try to block them by using other extensions or simply return with "back" button. TabBlock does not block any normal ads. Manifest v3 Update: The new approach in Manifest v3 prevents extensions from running in the background all the time, leading to a cold start that can significantly increase the time needed to close a new tab. However, this is purely a cosmetic downgrade - TabBlock now filters out all requests to new tabs instantly, in addition to its ability to close tabs. This means that even if you see a tab open, it won’t begin to load at all.