Does this really change the dialog height ? Since we dynamically add some elements when building the widget, I am not sure it will in the end change the real height (at least it doesn't change for me but might depend on your screen's dpi). I think there is room for a layout improvement, but if this really changes the dialog size for you, ok for me.

You are right. As one of the dynamically added widget has a fixed height, it increases the minimum height. We should just change it's size policy.