This is just a full-screen button added to the toolbar. It does exactly the same as the keyboard shortcuts (F11 on Windows or Cmd+Shift+F on Mac). You can change the icon and add/remove the full-screen function to the context menu.
To change the default settings — right-click on the extension and select “Options”. On the settings page you can:
* Change the icon to different color (to fit your Chrome theme or just because you don’t like the default black color) or even set our own icon
* Add/remove the Full Screen item in the context menu
This extension doesn’t need any special or dangerous permissions. It doesn’t read your data or sites. The only thing it does is to add the buttons to the toolbar and context menu.