I'm getting a video feed stutter on iPhone 11 iOS 11.3.1, Vuforia 8.6.10, Unity 2019.3. I'm not talking about jittery 3D objects, I mean the actual video background will jump up aperiodicaly. Error not present on an iPad Pro.
Setting the Camera Device Mode to MODE_OPTIMIZE_SPEED seems to have reduced the stuttering frequency to a small degree. Overheating is not an issue either, the stuttering occurs right as the app begins.