in my app, the world center seems to be off.
I'm using MRTK 2.7.0 with OpenXR 1.0.0 and Vuforia 9.8.8
On the Hololens, the Image Target gets recognized, but its position has a random fixed offset after the App initializes. The Setup is similar to the hololens2 Samples from the Asset store, but I cannot verify that the samples works as intended, because it doesn't compile.
I suspect, that the WorldCenterMode "Device" wich is enforced does not work properly? Extended Tracking and "Track Device Pose" are enabled.
the MRTK Maincamera under the Playspace has the VuforiaBehaviour and DefaultInitializationErrorHandler script attached. the Image marker are separate like in your samples.
running the app in the Editor with a Webcam works as expected. With that random offset on the Hololens, the ImageTargets are basically useless for me.
EDIT: I think I found the Culprit: OpenXR. Switching back to Windows Mixed Reality in the Project settings and using a default mixed reality profile in the MRTK solved the issue. This cost me hours! As far as I have understood, OpenXR is supposed to replace windows mixed reality in the future, which is why i opted for it.
tldr: DO NOT USE OPENXR!!!!!!!!!!!!!!!!!!!!!!!!!!