As shown in earlier versions of Windows, you can customize the taskbar in Windows 8.1 as well, including the way the taskbar buttons appear when you have opened more than one window.
Switch to another taskbar button display in Windows 8
The taskbar is a bar for launching and monitoring running applications and appears at the bottom of the desktop by default. To change the look or move it to another location, you must first unlock it.
To unlock the taskbar, right-click an empty space on the taskbar. If the ‘Lock taskbar’ option has a check mark, the taskbar is locked. You can unlock it by clicking on the same option again. this will also remove the mark.
To change the appearance of the taskbar buttons. Just go to the Taskbar Properties option and follow these simple steps.
Switch to another taskbar button display
Right-click on the space between the taskbar. Click Properties. Under the Taskbar tab, select one of the options from the Taskbar buttons:
You will see 3 options. Never combine, Combine when the taskbar is full and always combine, hide labels.
This setting displays each window as an individual, marked button, and never combines them, no matter how many windows are open. When more apps and windows are open, the buttons become smaller, and eventually the buttons scroll.
Combine when the taskbar is full
This setting displays each window as an individual, highlighted button. When the taskbar gets crowded, apps with multiple open windows collapse into a single app button. Clicking on the button displays a list of windows that are open.
Always combine, hide labels
This is the default setting. Each app appears as a single, unmarked button, even when multiple windows for that app are open. It uses very little task line space and therefore the most preferred setting.
Click OK when done.
That’s it! Now you see the changed appearance of the taskbar buttons – just like it was in Windows Vista or Windows XP.