ARFoundation - ARTrackedImageManager - Black Background

I was trying out the new samples from the GitHub Repository with ARFoundation 4.0 preview 3 in Unity 2020.1b7 on a Mac OSX 10.15.4 building for an Android 10 (Huawei P30Pro).

While things like just a ARSessionOrigin-Camera works and also the PointCloud-Samples, I only get a Black Background when I add/enable the “ARTrackedImageManager”-Script.

I had similar issues with previous version of AR Foundation while following the Unity Learn tutorial. I was able to deploy other AR apps that worked fine, but was getting the black screen without any compilation errors with AR Foundation samples.