I often need to select multiple objects, and then assign a common link to them. This used to work every time, but often in v3.x I find the link property is not available, even if links are supported by all the objects in the selection. (I say often because sometimes this does work as expected, and I can’t find a pattern for when it works and when not)
Ideally, the link property would be available even if some of the selected objects don’t support linking (the edit can simply be ignored for those objects). This is often the case if I need to marquee select a bunch of objects.