There may be times when the tabs appear in a horizontal layout …

… and other times when they disappear from sight, and you find them in a drop-down menu ...

This happens when the width of your browser window (and in some cases, your screen) is not adequate to display all of the tabs in a horizontal orientation. If this happens and you wish to see all of the tabs across the top of your work space, widen the browser window if you can. If this is not possible, rest assured that all of the tabs will still appear in the drop-down menu.