Taskbar Menu Vanishes
If your Taskbar Menu suddenly vanishes, like this:
You have probably inadvertently tapped your mouse in the empty space around the border. This happened to me for about two days. Very frustrating when I was trying to debug a program. It is running in what is known as Tiny Footprint Mode. Tiny Footprint, Big Frustration.
The way out is to click again at the top border of the window. It should then return like this:
Big screen version