I am experiencing an issue with Vuforia on the HoloLens where any time a scene is additively loaded on top of the main scene containing the ARCamera, the image targets do not align properly. I make heavy use of additively loaded scenes, so this is a major problem for me.
Additive scene loading with Vuforia had been working with Unity 2018.2.2f1 and Vuforia 7.1.35. In this setup, the VuforiaBehaviour WorldCenterMode was set to 'Camera'. However, in later versions 'Device' is the only option.
I have downloaded the Vuforia HoloLens Sample Project from the Asset Store and modified it so that in the image targets example, a simple scene is additively loaded after a few seconds. The image target aligns properly at first, but as soon as the second scene is additively loaded, it starts being misaligned. This is using Vuforia 8.0.10 with Unity 2018.2.10f1. I have attached this project.