After a recent Waze or Android update, when using Android's built-in split screen feature to display both Waze and another app at the same time, Waze's UI is very broken. The lower half of the screen is completely unreadable, and trying to interact with it is quite glitchy. Please look into qa'ing Android with split screen more thoroughly.

Note that this has nothing to do with Android Auto as I see many other posts regarding Android Auto specifically; this is using the built-in split screen feature by opening the current app list, tapping the Waze icon at the top of the screen, and selecting split screen (and then selecting the second app to split it with).