If true (Z9.0.1 linux here) then I hope this becomes a feature.

Currently, selecting non-contiguous items to copy/move to a collection by using the Control key navigates to any collections in the collections pane that these items are already in, with the effect of likely moving the target collection out of view and needing to be navigated to again.

This is a real problem if you have a lot of collections.

This Control key behaviour is surely now redundant anyway, as the Libraries and Collections button to the right of the item pane performs the same function more eloquently and makes the Z9-current behaviour obsolete.

Well, the problem is described in the italicised part of my first response.

In essence, as the problem is not manifest when selecting contiguous items but only non-adjacent ones, what should probably change is for the Control key not to have two distinct functions - one of them should be assigned to a different non-contentious key/key combination to keep the two actions separate.

(Note that I do not have a problem as such with a simple key accelerator highlighting which collections items might be in, that is clearly useful.)