[Babylon.js] The app freezes or is exited when entering/exiting immersive mode in one exemple after another or in multiple windows

[Softvision-RemusDranca]

[Affected Versions]:

• Firefox Reality version 12-142052346 (063f0dc).

[Affected Platforms]:

• Oculus Quest - Android 7.1.1
• HTC Vive Focus - Android 7.1.2
• Pico Neo2 - Android 8.1.0

[Prerequisites]:

• The Firefox Reality browser is open.

[Steps to reproduce]:

1. Navigate to https://doc.babylonjs.com/how_to/webxr_demos_and_examples.
2. Open one example after another and play them in immersive mode.
3. Observe the behavior.

[Expected results]:

• The examples are correctly played.

[Actual results]:

• The app is exited at one point or freezes.

[Notes]:

• The number of examples that need to be opened fluctuates from one attempt to another.
• The issue is also reproducible if multiple examples are opened in different windows.
• I wasn't able to save the videos where the app froze.
• I wasn't able to reproduce this issue following this steps in the production version (11), except some performance issues.
• Attachments for the issue:
  • Screen Recording: link.
  • Logcat: link.

[AleixCat]

Hi @Softvision-RemusDranca, Recently I found a similar issue and with some researching I found a solution to make it work.

As far as I know, Firefox Reality uses a deprecated version of WebVR, now called WebXR and Babylon in their examples uses XR functionalities that block you from entering the scene in VR mode. Until the new version of WebXR is not implemented to Firefox reality, you can force Babylon to use WebVR by typing this line of code when creating the VR setup in the playground examples.

var vrHelper = scene.createDefaultVRExperience({createDeviceOrientationCamera:false, useXR: false});

Basically, you have to turn off useXR property. Maybe some functionalities it won't work as intended but at least you can enter in immersive mode.

Here our actual working example, I'ts a 360 HLS live video viewer: https://www.babylonjs-playground.com/#9FSDC7#173