For the new multiselect it seems that you can only resize it horizontally, and not create a larger select box like the prior version of the multiselect. For example in the prior version I could have a larger box (image 1 below) which if I expect there to be more than a few items selected is much easier to navigate than the new smaller version (image 2). I see that it will auto expand, but for setting up the layout is would be cleaner to just have it start at the larger size then expanding into empty space.
Image 1
Image 2
