None.
utf8 [on|off [on|off]]
Change the encoding used in the current window. If utf8 is enabled,
the strings sent to the window will be UTF-8 encoded and vice versa.
Omitting the parameter toggles the setting. If a second parameter is
given, the display's encoding is also changed (this should rather be done
with screen's -U option). See also defutf8,
which changes the default setting of a new window.
None yet.