Vuforia engine: vuforia-sdk-ios-7-5-26

I reused the source code of the provided sample project 'vuforia-samples-core-ios-7-5-26 CloudReco'

To switch to another function after using the AR camera, I called 'stopAR' of SampleApplicationSession.

the camera stopped, but it appears like it's running on the main thread, causing latency of the overall operation of the app.

vuforia-samples-core-ios-7-5-26 We have confirmed that the same problem occurs in the project.

I'd like to know Whether there is another way to stop the AR Camera.

Alternatively, please let me know if there is another solution