WebCamTexture nullpointerexception

I am trying to build an app which uses webcam.

I am applying the webCamTexture on a raw image.

I am trying to run this on webGL.

I have done all the fact checks and applied all the safety checks.

 public RawImage rawimage;
 
 void Start () {
        
         WebCamDevice backCameraDevice;
         Debug.Log("code started");
         WebCamDevice[] devices = WebCamTexture.devices;
         for (int i = 0; i < devices.Length; i++)
             Debug.Log(devices[i].name);
 
         if (WebCamTexture.devices.Length == 0)
         {
             Debug.Log("No devices cameras found");
             return;
         }
 
         backCameraDevice = WebCamTexture.devices[0];
         Debug.Log(backCameraDevice.name);
 
         WebCamTexture webcamTexture = new  WebCamTexture(backCameraDevice.name);
         webcamTexture.requestedWidth = 150;
         webcamTexture.requestedHeight = 150;
 
         rawimage.texture = webcamTexture;
         
         rawimage.material.mainTexture = webcamTexture;
         webcamTexture.Play();
   
     }

I am getting a null pointer exception when I try to run this.

Any help would be great. Please let me know how can I provide more information if needed