iphone error: undefined is not an object

[zackhalil]

Describe the bug
When I start the scanner only on iphone it gives an error.

To Reproduce
let qrboxFunction = function(viewfinderWidth, viewfinderHeight) {
let minEdgePercentage = 0.85; //%
let minEdgeSize = Math.min(viewfinderWidth, viewfinderHeight);
let qrboxSize = Math.floor(minEdgeSize * minEdgePercentage);
return {
width: qrboxSize,
height: qrboxSize
};
}

  html5QrcodeScanner = new Html5QrcodeScanner("scanner", { 
     fps: 50, 
     qrbox: qrboxFunction,
     rememberLastUsedCamera: true,
     showZoomSliderIfSupported: true,
     showTorchButtonIfSupported : true,
     supportedScanTypes: [Html5QrcodeScanType.SCAN_TYPE_CAMERA]
  });

Expected behavior
expecting no error and the buttons underneath to hide and show only Stop Scanning button

Screenshots

Smartphone (please complete the following information):
Issue seems to be in iphone only. tested on iphone 14 pro

[zackhalil]

Seems related to zoom... can workaround it by

showZoomSliderIfSupported: !(/iPad|iPhone|iPod/.test(navigator.platform))