Excel window is minimized, or very tiny and impossible to close

If you cannot close an Excel window, or you can't even find it anywhere on your monitor/screen, it might be a bug that we're working on.

This tiny window cannot be found or closed with a mouse, so you have to use a keyboard shortcut instead.

When the window is 'in focus' or 'active' after you click on it in the Taskbar at the bottom of the screen, press ALT + SPACE and a drop-down will come up.

Press "X" next and the window will be maximized. You can close it now.