When Emacs is invoked on a window system, the new command-line options
`--fullwidth', `--fullheight', and `--fullscreen' produce a frame
whose width, height, or both width and height take up the entire
-screen size. (For now, this works only on GNU and Unix systems, and
-not with every window manager.)
+screen size. (For now, this does not work with some window managers.)
** Info-index finally offers completion.