procedure TForm1.FormCreate(Sender: TObject);
begin
SetWindowLong(
Handle,
GWL_STYLE,
not (WS_THICKFRAME) and GetWindowLong(Handle, GWL_STYLE) or Integer(WS_POPUP)
);
SetWindowPos(Handle, 0, 0, 0, 1920, 1080, SWP_NOZORDER or SWP_NOMOVE);
end;