It displays annoying red circle in the corner, or sometimes a big red rectangle, which shows how many counters it blocked. There is no way to switch it off.

PS: with respect to developer's response, I was unable to find the ways to get to settings. When I click the icon, I don't get to settings. Users should not spend time discover how to get rid of annoying alerts (any alert is annoying if it is on the area alotted for displaying webpages), such alerts should be off by default, and getting to settings should be intuitive.