Hi, your question was posted from a Windows PC but also marked as a question about the new Firefox OS for mobile phones. Let's see whether I can cover both of those. (1) Windows You have a choice of menu systems: the classic bar (File, Edit, View...) and the orange Firefox button leading to a compact two-column menu. * If you are displaying the orange Firefox button, you can tap the Alt key or the F10 key to display the classic menu bar temporarily. * To turn the classic menu bar on and off, you can right-click a blank area of the tab bar or the new tab ("+") button and use the short toolbar list to show and hide the menu bar and various toolbars. * If you can't see any toolbars, you might be in full screen mode. The F11 key will switch between normal and full screen views. (2) Firefox OS Probably you need to open the Settings app.