If we setup a viewport and tick the “Preserve scale on resize” box, current view of the model and scale are preserved.
If we setup a preset scale, the “Preserve scale on resize” box get’s active by default wich is good. If we untick the box, current view and scale of the model are preserved and we can scale the model and viewport as if they are connected.
However, if we setup a preset scale, or if we tick the “Preserve scale on resize box”, and then adjust the framing of the model, as soon as we untick the box we loose model position on the viewport and even scale.
They should be kept.