Hello,

When the ctwm window manager is restarted, the emacs fullscreen frame,
set with `F11' key, shifts up by approximately 50 pixels and shows the
desktop background.  The right edge of the frame shifts a little to the
left.  Expect the fullscreen frame to remain unchanged.

To demonstrate,

 1. start, `emacs -Q'
 2. enlarge frame to fullscreen, `F11'
 3. call, `Restart CTWM' from window manager menu on X
 4. see the fullscreen frame bottom edge is shifted up 50 pixels approximately

 X. expect to see no change to fullscreen frame when ctwm restarts
    for comparison, a fullscreen xterm frame remains unchanged when ctwm restarts

=> http://sdf.org/~van.ly/img/emacs-fullscreen-frame-0.webp .
=> http://sdf.org/~van.ly/img/emacs-fullscreen-frame-1-shifts-up.webp .

=> http://mail-index.netbsd.org/netbsd-users/2024/11/23/msg031998.html discussion about shifted fullscreen frame behavior