set-window-id-background! -- Set the background color of X11 window with id WINID to BG.
Synopsis
(set-window-id-background! bg #&optional winid)
Description
Set the background color of X11 window with id winid to bg.
This is not necessarily persistent. In particular, if you set
the background color of a window decoration, that decoration
will revert to its usual color. See also window-decoration-ids.