When searching for a specific plugin you can type the beginning or a part of the plugin name to filter only for matching plugins. Then in most other programs (music related or not) you can use the up and down keys to select between the remaining entries and then select the desired plugin with ENTER. But in Cubase after typing at the keyboard you have to switch back to using the mouse to make this final selection. That’s more complicated than necessary and much slower. It would nice to have this also in Cubase.
I was told some years ago by a Steinberg employee this was not possible because the search field and the list are two different objects, but I can tell: This is still doable (I’m a software developer myself). So please: Try harder! 
No… I can use the arrow keys
I forgot to mention that I mean selecting an plugin in the mixer, for an insert. Up & down doesn’t work there.
Did you mean instruments or where does this work?
PS: How can I quote a reply? I’m too stupid to find that, it seems…
you have to press “tab” to change the target window…
That shouldn’t be necessary. So called “drop down lists” normally don’t need that extra step. Of course that’s not a big difference but I’m so used to not need that extra step…
Thanks for the clarification anyway!
Just get used to smashing tab first, I do this in a split second and don’t even think about it.
I also do agree that its stupid, if you have selected with your mouse this object, you should freely be able to scroll through without the extra tabbing step, but alas, they haven’t changed it till now and the workaround is stupid easy once you have done it a few times, you will be flying.