Trying to get ARCore going but I find that the example files do not appear as expected (for example HelloAR appears as white screen) both in the Unity editor and on the Android phone (Motorola G7). Googling this symptom comes up with lots of instances with lots of different suggested solutions (sounds like a common symptom with lots of possible causes). I've tried most of the solutions I've read about but haven't gotten anywhere with solving it. I have Unity 2019.1.2f1 on Mac OS 10.14.4. I seem to be able to get other (non ARCore projects) to appear as expected in the editor and on the Android phone. Any suggestions for how to proceed ? Any ideas most welcome. Thanks in advance.