Consider the following situation: you have a menu bar (full screen window),
you make a certain selection and you get another window of a fixed size in
the foreground, say x by y. If you now select in the menu-bar of that second
window a certain option, that second window should become larger, say a
size of a by b, maybe with a scrollbar.

How to get this `auto-resizing'?
Is it possible to let the scrollbar appear, only if the text wouldn't fit in
the (enlarged) window?

Regards