⤷ Move form by client area

If you want, that user can move your form by client area, then use WM_NCHITTEST handler to achieve this cool effect:
In the Forms private declarations add this

  procedure WMNCHitTest(var Msg: TWMNCHitTest);
message WM_NCHITTEST;
Create handler for this message with this code:

procedure TForm1.WMNCHitTest(var Msg: TWMNCHitTest);
begin
 DefaultHandler(Msg);
 if Msg.Result=HTCLIENT then
   Msg.Result:=HTCAPTION;
end;
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