Buttons in a runtime created FMXPopup seem to ignore the Layout property.
Maybe I'm doing something wrong.
Example code (new Multi-Device Application with 1 standard button)
procedure TForm1.Button1Click(Sender: TObject);
var
pop: TTMSFMXPopup;
btn : TTMSFMXPopupButton;
begin
pop := TTMSFMXPopup.Create(nil);
try
btn := pop.FooterButtons.Add;
btn.Text := 'Cancel';
btn.Layout := TTMSFMXBarButtonShapeLayout.slPointer;
pop.ShowPopup(Button1, True);
finally
pop.Free;
end;
end;