Eike Hein fixed a regression (#397779) that made it unintuitive to navigate Kicker with the arrow keys. The fix unfortunately didn't make it into 5.13.5, and so this is a request/wish for it to be backported to Cosmic. I know it's a small bug, but I think it is an annoying one for users of Kicker, and the fix makes the navigation consistent with Kickoff's.
The commit: https://cgit.kde.org/plasma-desktop.git/commit/?id=1692ae244bc5229df78df2d5ba2e76418362cb50
And phab: https://phabricator.kde.org/D15286