Frame is a structure.
Each time you click on the links inside the frame, your browser logs it as an event. So after a while of navigating the content, you might need to click on Back button on the toolbar several times to quit the frame. To shorten this manipulation, you should add the front page to your favorites then you can use it as a shortcut. Either pull down the Favorites menu or click on the Favorites button on the toolbar. The title of that current page will be added to the list From anywhere, by opening the list and highlighting that title, you will move to that page.