AsyncGPUReadback.Request - "This GfxDevice does not support asynchronous readback"

I'm trying to make screenshots in my Quest app without hitches, but I'm getting this error, despite AsyncGPUReadback.Request supposedly working fine on Android. The code is fairly simple, every second or so it gets a RenderTexture, captures a screenshot to it, then does the async readback to transfer the screenshot to the CPU where I can proceed to turn it into a JPG:

   IEnumerator TakeScreenshots()
    {
        while (recording)
        {
            yield return new WaitForSeconds(1.0f);
            if (recording)
            {
                yield return new WaitForEndOfFrame();

                RenderTexture tex = RenderTexture.GetTemporary(Screen.width, Screen.height, 0, RenderTextureFormat.ARGB32);
                ScreenCapture.CaptureScreenshotIntoRenderTexture(tex);
                AsyncGPUReadback.Request(tex, 0, TextureFormat.ARGB32, ConvertToJPGAndStore);
                RenderTexture.ReleaseTemporary(tex);

                //                Texture2D texture = ScreenCapture.CaptureScreenshotAsTexture();
                //               screenshots.Add(timer, texture.EncodeToJPG());
            }
        }
    }

This is using OpenGL ES 3. Any ideas?

Did you ever work this out?

"This GfxDevice does not support asynchronous readback" I got this error when i was using Zxing to Scan Qr and Barcode. To resolve this check out the Graphics API's in Project Settings -> Player -> Other Settings , if you see the API to be "deprecated" then click on + and add a new API , then remove the old API by clicking on - . This solved my problem.