⤷ Hide forms and taskbar button

For this purpose it is necessary to change the type of the created form in the FormCreate handler (if windows have WS_EX_TOOLWINDOW style, then these windows are not displayed on Task Bar) and create handler for the FormClose event for preventing closing the window.

procedure TForm1.FormCreate(Sender: TObject);
begin
  SetWindowLong(Application.Handle,GWL_EXSTYLE,WS_EX_TOOLWINDOW);
end;

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
  Action:=caNone;
  Form1.Hide;
end;
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