Complex sentence: In addition, in Windows 8 and Windows 8.1 RTM, they are not shown on the Windows taskbar when they run, but on a dedicated app switcher on the left side of the screen.
Split into simpler sentences: In addition, in Windows 8 and Windows 8.1 RTM, they do not show up on Windows taskbar when they run. Instead, they appear on a dedicated app switcher on the left side of the screen.