maximum number of lines; @code{nil} means do not resize the minibuffer
window automatically. The default value is 0.25.
-@vindex minibuffer-scroll-overlap
- Scrolling works specially in the minibuffer window. When the
-minibuffer is just one line high, and it contains a long line of text
-that won't fit on the screen, scrolling automatically maintains an
-overlap of a certain number of characters from one continuation line to
-the next. The variable @code{minibuffer-scroll-overlap} specifies how
-many characters of overlap; the default is 20.
-
If while in the minibuffer you issue a command that displays help text
of any sort in another window, you can use the @kbd{C-M-v} command while
in the minibuffer to scroll the help text. This lasts until you exit