When you enter a new area with a talking head this addon will, by default, completely suppress it. There is no indication that this is working you will just never see "Talking Heads" again.
Talking Heads are the popups that show a dialogue of the character involved with that world quest. It takes up a large portion of the screen and sticks around a little too long. If you don't like those and want to completely eliminate them, then this AddOn will do it.
There are other addons that offer customization if that is what you want. I took the AddOn called 'BeQuiet' and removed all the functionality to have this bare bones minimum AddOn. I, personally, never want to see these talking heads so I wrote this addon to deal with that.
You can test that it is working by doing world quests (or any other activity with talking heads) and you will notice they no longer appear.
If you don't want this AddOn to block talking head frames anymore then go to ESC->AddOns and disable HideBlizzardTalkingHead. There is no need for a minimap button or any interface options.