Allow seeing and snapping to symbol copies when editing master symbol

Symbols are a great feature for tessellation but it would be a lot better if I would see the changes I make affecting the entire set of symbols at the same time. Every time I enter Edit Master mode, the rest of the stuff disappears and only the master symbol is visible. It would help if I would also see the copies of the symbol, so I could see how the tessellation fits together. Allowing to snap to the copies' objects and nodes would help as well, allowing for more precise alignment throughout the entire tessellating pattern. Thanks.