A frame configuration records the current arrangement of frames,
all their properties, and the window configuration of each one.
(See Window Configurations.)
— Function: current-frame-configuration
This function returns a frame configuration list that describes
the current arrangement of frames and their contents.
This function restores the state of frames described in
configuration.
Ordinarily, this function deletes all existing frames not listed in
configuration. But if nodelete is non-nil, the
unwanted frames are iconified instead.