Uses Messages;
...
public
procedure WMNCHitTest(var Message: TWMNCHitTest); message;
WM_NCHITTEST;
end;
...
procedure TForm1.WMNCHitTest(var Message: TWMNCHitTest);
var
P : TPoint;
begin
inherited;
P := ScreenToClient(SmallPointToPoint(Message.Pos));
with imgTitle do
if (P.X >= Left) and (P.X < Left + Width) and (P.Y >= Top)
and (P.Y < Top + Height) then
Message.Result := htCaption;
end;

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