QR-Tracking: Calling RequestAccessAsnyc in Play-Mode Causes Crash in Subsequent Runs

[SebKranz]

Calling RequestAccessAsync from mixedreality.QR when running in the editor, for example during Holographic Remoting, causes a crash when the editor is stopped and then started again.

In unity 2020.xx, crashes occur every 2-5 plays.
In unity 2021.xx crashes occur before every second play (play -> stop -> play -> crash).

chgatla-microsoft/QRTracking#46 reports this in more detail.
#326 mentions a potential fix, but didn't help in my case.

microsoft/MixedReality-QRCode-Sample#6 might be connected, as both crashes occur when tracking is restarted.

The crash occurs regardless of whether Holographic Remoting was used in the previous session. Simply calling RequestAccessAsync from Unity creates the necessary conditions.

[typride]

I've pinged some people that may be able to help. Thanks!

[wbueschel]

Is there any news on this? I experience the same problem and it makes working with QR codes a pain.

[cirvladimir]

I'm having the same issue. In the meantime, a workaround would be nice. An intermediate library could be written on top of the QR code library which caches the QR code locations and then skips the actual QR library altogether. Does anyone have something like this?

[pablodiazv]

My problem is similar, first time I start remote debugging all works fine, but the second time not crash but QR detection not work. Has anyone find a solution?