Multi touch problems with WebGL

Hello, i'm trying to implement a simple orbit camea that can rotate and zoom in a scene. I followed some tutorials and i can run my program without any problems on windows if i build it as a PC Standalone. If i build it as WebGL my camera still correctly works with a single touch (rotation) , with multi touch i have a strange behaviour.. Difficult to explain but it zoomsin and out even if i do not move the fingers. Is king of "fuzzy". It happens with Firefox and Chrome, the browsers i have tested.

This is my code.. using System.Collections; using System.Collections.Generic; using UnityEngine;

 public class CameraOrbitTouch : MonoBehaviour {
 
     protected Transform _XForm_Camera;
     protected Transform _XForm_Parent;
 
     protected Vector3 _LocalRotation;
     protected float _CameraDistance = 10f;
     
     // The rate of change of the field of view in perspective mode.
     public float perspectiveZoomSpeed = 0.2f;    
 
     public float OrbitDampening = 30f;
     public float ScrollDampening = 18f;
 
     public bool CameraDisabled = false;
 
 
     // Use this for initialization
     void Start() {
         this._XForm_Camera = this.transform;
         this._XForm_Parent = this.transform.parent;
     }
 
 
     void LateUpdate() {
         if (Input.GetKeyDown(KeyCode.LeftShift))
             CameraDisabled = !CameraDisabled;
 
         if (!CameraDisabled)
         {
             //Rotation of the Camera based on Mouse Coordinates
             if (Input.touchCount == 1 && Input.GetTouch(0).phase == TouchPhase.Moved)
             {
                 _LocalRotation.x += Input.touches[0].deltaPosition.x ;
                 _LocalRotation.y += Input.touches[0].deltaPosition.y;
 
                 //Clamp the y Rotation to horizon and not flipping over at the top
                 if (_LocalRotation.y < 0f)
                     _LocalRotation.y = 0f;
                 else if (_LocalRotation.y > 90f)
                     _LocalRotation.y = 90f;
                 
                 
             }
           
             //Zooming Input from our Mouse Scroll Wheel
             if (Input.touchCount == 2 && Input.GetTouch(0).phase == TouchPhase.Moved && Input.GetTouch(1).phase == TouchPhase.Moved)
             {
                 // Store both touches.
                 Touch touchZero = Input.GetTouch(0);
                 Touch touchOne = Input.GetTouch(1);
                 
                 // Find the position in the previous frame of each touch.
                 Vector2 touchZeroPrevPos = touchZero.position - touchZero.deltaPosition;
                 Vector2 touchOnePrevPos = touchOne.position - touchOne.deltaPosition;
                 
                 // Find the magnitude of the vector (the distance) between the touches in each frame.
                 float prevTouchDeltaMag = (touchZeroPrevPos - touchOnePrevPos).magnitude;
                 float touchDeltaMag = (touchZero.position - touchOne.position).magnitude;
 
                 // Find the difference in the distances between each frame.
                 float deltaMagnitudeDiff = (prevTouchDeltaMag - touchDeltaMag);
                 
                 //this._CameraDistance += deltaMagnitudeDiff * -1f;
                 this._CameraDistance += deltaMagnitudeDiff * perspectiveZoomSpeed;
                 this._CameraDistance = Mathf.Clamp(this._CameraDistance, 1.5f, 100f);
             }
         }
 
         //Actual Camera Rig Transformations
         Quaternion QT = Quaternion.Euler(_LocalRotation.y, _LocalRotation.x, 0);
         this._XForm_Parent.rotation = Quaternion.Lerp(this._XForm_Parent.rotation, QT, Time.deltaTime * OrbitDampening);
 
         if ( this._XForm_Camera.localPosition.z != this._CameraDistance * -1f )
         {
             this._XForm_Camera.localPosition = new Vector3(0f, 0f, Mathf.Lerp(this._XForm_Camera.localPosition.z, this._CameraDistance * -1f, Time.deltaTime * ScrollDampening));
         }
     }
 }

Can someone can tell me why this is happening? Have my code some errors? There is some kind of incompatibility with WebGL and multi touch? Thans for your time and answers